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PROSPECTUS SUPPLEMENT

(To Prospectus dated June 20, 2000)

Interest payable annually on November 11

IBM may not redeem the Notes prior to maturity unless certain events occur involving changes in United States taxation, as set forth in this prospectus supplement.
Application will be made to list the Notes on the New York Stock Exchange.
 
   Price to
Public
   Underwriting
Discounts and
Commissions
   Proceeds to
Company
Per Note   99.769%   0.225%   99.544%
Total   €598,614,000   €1,350,000   €597,264,000

The Securities and Exchange Commission and state securities regulators have not approved or disapproved of these securities, or determined if this prospectus supplement or the accompanying prospectus are truthful or complete. Any representation to the contrary is a criminal offense.

The Underwriters expect to deliver the Notes to purchasers in book-entry form only through the Depository Trust Company, Clearstream Banking or the Euroclear System, as the case may be, on November 13, 2006.

Joint Bookrunners

BNP PARIBAS   Deutsche Bank   UBS Investment Bank

Co-Managers

  Barclays Capital  

 
Goldman Sachs International
 

 
JPMorgan
 

 
Morgan Stanley
 

 
Santander Investment
 


November 6, 2006

        You should rely only on the information contained in or incorporated by reference in this prospectus supplement and the accompanying prospectus. We have not authorized anyone to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information contained in this prospectus supplement or the accompanying prospectus is accurate as of any date other than the date on the front of this prospectus supplement.

        The Notes are offered globally for sale in those jurisdictions in the United States, Canada, Europe, Asia and elsewhere where it is lawful to make such offers. See "Offering Restrictions."


TABLE OF CONTENTS

 
   Page
Prospectus Supplement

International Business Machines Corporation
 
S-3
Use of Proceeds   S-4
Capitalization   S-4
Ratio of Income From Continuing Operations to Fixed Charges   S-4
Description of Notes   S-5
United States Taxation   S-13
Underwriting   S-19
Offering Restrictions   S-20
Legal Opinions   S-22
Experts   S-23

Prospectus
Summary   3
Ratios of Earnings to Fixed Charges and Earnings to Combined Fixed Charges and Preferred Stock Dividends   4
Where You Can Find More Information   5
Description of the Company   6
Use of Proceeds   6
Description of the Debt Securities   6
Description of the Preferred Stock   18
Description of the Depositary Shares   19
Description of the Capital Stock   22
Description of the Warrants   22
Plan of Distribution   24
Legal Opinions   24
Experts   24

        The distribution of this prospectus supplement and prospectus and the offering of the Notes in certain jurisdictions may be restricted by law. Persons into whose possession this prospectus supplement and the prospectus come should inform themselves about and observe any such restrictions. This prospectus supplement and the prospectus do not constitute, and may not be used in connection with an offer or solicitation by anyone in any jurisdiction in which such offer or solicitation is not authorized or in which the person making such offer or solicitation is not qualified to do so or to any person to whom it is unlawful to make such offer or solicitation. See "Offering Restrictions."

        References herein to "$" and "dollars" are to the currency of the United States. References to "€" and "euro" are to the currency of the member states of the European Monetery Union that have adopted or that adopt the single currency in accordance with the treaty establishing the European Community, as amended by the Treaty on European Union. The financial information presented herein has been prepared in accordance with Generally Accepted Accounting Principles in the United States.

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INTERNATIONAL BUSINESS MACHINES CORPORATION

        International Business Machines Corporation (IBM) was incorporated in the State of New York on June 16, 1911, as the Computing-Tabulating-Recording Co. (C-T-R), a consolidation of the Computing Scale Co. of America, the Tabulating Machine Co., and The International Time Recording Co. of New York. Since that time, IBM has focused on the intersection of business insight and technological invention, and its operations and aims have been international in nature. This was signaled over 80 years ago, in 1924, when C-T-R changed its name to International Business Machines Corporation. And it continues today: IBM is the largest information technology company in the world, the world's largest business and technology services company, the world's largest consulting services organization, the world's largest information technology research organization, and the world's largest financier of information technology.

        IBM is an innovation company, serving the needs of enterprises and institutions worldwide. IBM seeks to deliver clients success by enabling their own capacity to innovate, so that they may differentiate their organizations to create unique competitive advantage.

        To help its clients achieve growth, productivity, efficiency, and the realization of greater value through innovation, IBM draws upon the world's leading systems, software and services capabilities to turn enterprises of all sizes, in every major industry, into on demand businesses. An on demand business is an enterprise that is integrated end-to-end, and, with its business ecosystems of partners, suppliers and clients, is able to manage that extended network dynamically to address new opportunities, respond to changes in demand or threats to its business, enhance flexibility, speed execution and ultimately achieve profitable growth.

        In IBM's view, being on demand is the most comprehensive way to enable a company to innovate—and thus differentiate itself—consistently over time. IBM views enterprise innovation not only in terms of products and services, but across all dimensions of a business: its business processes, business model, management systems, culture and role in society.

        IBM is the ultimate parent for a group of companies including subsidiaries and other organizations, operating in over 150 countries around the world. Organizationally, the company's major operations comprise a Global Technology Services segment; a Global Business Services segment; a Systems and Technology Group; a Software segment; and a Global Financing segment. The segments are determined based on several factors, including customer base, homogeneity of products, technology and delivery channels.

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USE OF PROCEEDS

        The net proceeds from the sale of the Notes after deducting expenses to be paid by IBM are estimated to be €597 million and will be used for general corporate purposes.


CAPITALIZATION

        The following table sets forth the consolidated capitalization of IBM at September 30, 2006, and as adjusted to give effect to the issuance of the Notes offered hereby.

 
   September 30, 2006
  
 
   Outstanding
   As Adjusted
  
 
   (Dollars in millions)

  
Short-term debt   $ 8,555   $ 8,555  
   
 
 
Long-term debt:              
  International Business Machines Corporation     12,492     13,255  
  Consolidated subsidiaries     944     944  
   
 
 
    Total long-term debt   $ 13,436   $ 14,199  
   
 
 

Stockholders' equity
 
 
 
 
 
 
 
  Common stock—par value $0.20 per share and additional paid-in capital     30,257     30,257  
    Shares authorized: 4,687,500,000              
    Shares issued: 1,995,246,297              
  Retained earnings     49,402     49,402  
  Treasury stock—at cost     (45,096 )   (45,096 )
    Shares: 488,894,453              
  Accumulated gains and (losses) not affecting retained earnings     (315 )   (315 )
   
 
 
    Total stockholders' equity     34,248     34,248  
   
 
 
    Total capitalization   $ 56,239   $ 57,002  
   
 
 

Notes:—

        From January 31, 1995 through September 30, 2006 IBM repurchased approximately $74.1 billion of its capital stock under a series of authorizations from IBM's Board of Directors that total $76.5 billion.


RATIO OF INCOME FROM CONTINUING OPERATIONS TO FIXED CHARGES

        The ratio of income from continuing operations to fixed charges has been computed by dividing income from continuing operations before income taxes (which excludes (a) amortization of capitalized interest and (b) IBM's share in the income and losses of less than 50% owned affiliates) and fixed charges (excluding capitalized interest) by fixed charges. "Fixed charges" consist of interest expense, capitalized interest and that portion of rental expense deemed to be representative of interest.

 
    
   Year Ended December 31,
 
   Nine Months Ended
September 30, 2006
   2005
   2004
   2003
   2002
   2001
Ratio of income from continuing operations to fixed charges   9.0   11.1   11.0   9.3   5.6   6.9

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DESCRIPTION OF NOTES

        The following description of the particular terms of the Notes supplements, and to the extent inconsistent, replaces the description of the general terms and provisions of the debt securities set forth in the prospectus.

General

        The Notes will be issued under an Indenture (the "Senior Indenture") dated as of October 1, 1993, between IBM and The Bank of New York, as Trustee, as supplemented by the First Supplemental Indenture dated as of December 15, 1995, filed as an exhibit to the Registration Statement of which the accompanying prospectus is a part. The Notes will be unsecured and will have the same rank as all of IBM's other unsecured and unsubordinated debt. The Notes will bear interest from November 13, 2006, at the rate of interest stated on the cover page of this prospectus supplement. Interest on the Notes will be payable annually on November 11 commencing November 11, 2007, to the persons in whose names such securities are registered at the close of business on the October 27 preceding each November 11, payable in equal annual installments. Interest on the Notes will be computed on the basis of the actual number of days in the period for which interest is being calculated and the actual number of days from and including the last date on which interest was paid on the Notes (or November 13, 2006 if no interest has been paid on the Notes), to but excluding the next scheduled interest payment date. This payment convention is referred to as ACTUAL/ACTUAL (ISMA) as defined in the rulebook of the International Capital Market Association. The Notes will mature on November 11, 2011.

        The Notes are not subject to redemption prior to maturity unless certain events occur involving United States taxation. If any of these special tax events do occur, the Notes may be redeemed at a redemption price of 100% of their principal amount plus accrued and unpaid interest to the date of redemption. See "Description of Notes—Redemption for Tax Reasons." The Notes will be subject to defeasance and covenant defeasance as provided in "Description of the Debt Securities—Satisfaction and Discharge; Defeasance" in the accompanying prospectus. The Notes will be issued in denominations of €50,000 and integral multiples thereof.

        IBM may, without the consent of the holders of Notes, issue additional notes having the same ranking and the same interest rate, maturity and other terms as the Notes, provided however, that no such additional notes may be issued unless such additional notes are fungible with the Notes for U.S. federal income tax purposes. Any additional notes having such similar terms, together with the Notes, will constitute a single series of notes under the Senior Indenture. No additional notes may be issued if an event of default has occurred with respect to the Notes.

        The currency of payment for the Notes is the euro. However, when interests in the Notes are held through DTC, all payments in respect of such DTC Notes will be made in U.S. dollars, unless the holder of a beneficial interest in the DTC Notes elects to receive payment in euro. See "—Issuance in Euro."

Issuance in Euro

        Initial holders will be required to pay for the Notes in euro. The Bank of New York, as Trustee, is prepared to arrange for the conversion of U.S. dollars into euro to facilitate payment for the Notes by U.S. purchasers. Each conversion will be made by The Bank of New York on the terms and subject to the conditions, limitations and charges as The Bank of New York may from time to time establish in accordance with regular foreign exchange practices, and subject to United States laws and regulations. All costs of conversion will be borne by the holder.

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        Notes which are offered and sold in the United States (the DTC Notes) will be represented by beneficial interests in a fully registered permanent global Note (the DTC global Note) which will be deposited with a custodian for, and registered in the name of Cede & Co. as nominee for DTC. While interests in the DTC Notes are held through the DTC global Note, all payments in respect of such Notes will be made in U.S. dollars, except as otherwise provided in this section.

        The paying agent will determine the amount of any U.S. dollar payment based on the highest firm bid quotation, expressed in U.S. dollars, that it receives at approximately 11:00 a.m., Brussels time two Business Days before the applicable payment date (if no rate is quoted on that date, the paying agent will use the last date on which the rate was quoted). To determine the highest quote, the paying agent will request quotes from three (or, if three are not available, then two) recognized foreign exchange dealers in London (which may include the Underwriters, their affiliates or the paying agent) for the purchase, and settlement on the applicable payment date, of the total amount of euro then payable. The holder will be responsible for all currency exchange costs, such amount to be deducted from the U.S. dollar payments. If no bid quotations are available, IBM will make payments in euro, unless the euro is unavailable due to the imposition of exchange controls or other circumstances beyond IBM's control. In that case, IBM will make payments as described under "Exchange Rates and Exchange Controls."

        The holder of a beneficial interest in the DTC Notes may elect to receive a payment or payments in euro by notifying the DTC participant through which its Notes are held on or prior to the applicable Record Date of (1) the holder's election to receive all or a portion of the payment in euro, and (2) wire transfer instructions to a euro account located outside of the United States. DTC must be notified of an election and wire transfer instructions (1) on or prior to the third New York Business Day (as defined below) after the Record Date for any payment of interest, and (2) on or prior to the fifth New York Business Day prior to the date for any payment of principal. DTC will notify the paying agent of an election and wire transfer instructions (1) on or prior to 5:00 p.m. New York City time on the fifth New York Business Day after the Record Date for any payment of interest, and (2) on or prior to 5:00 p.m. New York City time on the third New York Business Day prior to the date for any payment of principal. If complete instructions are forwarded to DTC through DTC participants and by DTC to the paying agent on or prior to such dates, such holder will receive payment in euro outside of DTC; otherwise, only U.S. dollar payments will be made by the paying agent to DTC.

        The term "Business Day" means any day other than a Saturday or Sunday that is (1) not a day on which banking institutions are authorized or required by law or executive order to close in The City of New York, and (2) a TARGET Settlement Day.

        The term "New York Business Day" means any day other than a Saturday or Sunday or a day on which banking institutions in the City of New York are authorized or required by law or executive order to close.

        As of December 30, 2005, the euro/U.S.$ rate of exchange was €0.84445/U.S.$1 and as of November 6, 2006, the euro/U.S.$ rate of exchange was €0.78676/U.S.$1.

Exchange Rates and Exchange Controls

        An investment in the Notes by a purchaser whose home currency is not the euro entails significant risks. These risks include the possibility of significant changes in rates of exchange between the holder's home currency and the euro and the possibility of the imposition or modification of foreign exchange controls. These risks generally depend on factors over which IBM has no control, such as economic and political events and the supply of and demand for the relevant currencies. In recent years, rates of exchange between the euro and certain currencies have been highly volatile, and each holder should be aware that volatility may occur in the future. Fluctuations in any particular exchange rate that have occurred in the past, however, are not necessarily indicative of fluctuations in the rate that may occur

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during the term of the Notes. Depreciation of the euro against the holder's home currency would result in a decrease in the effective yield of such Note below its coupon rate and, in certain circumstances, could result in a loss to the holder.

        If the euro is unavailable to IBM due to the imposition of exchange controls or other circumstances beyond IBM's control or the euro is no longer used by the member states of the European Monetary Union that have adopted the euro as their currency or for the settlement of transactions by public institutions of or within the international banking community, then all payments in respect of such Note will be made in U.S. dollars until such currency is again available to IBM or so used. The amount payable on any date in euro will be converted into U.S. dollars on the basis of the most recently available market exchange rate for the euro. Any payment in respect of such Note so made in U.S. dollars will not constitute an event of default under the Senior Indenture.

Applicable Law and Foreign Currency Judgments

        The Notes will be governed by and construed in accordance with the internal laws of the State of New York. Courts in the United States customarily have not rendered judgments for money damages denominated in any currency other than the U.S. dollar.

Payments of Additional Amounts

        IBM will, subject to the exceptions and limitations set forth below, pay as additional interest on the Notes such additional amounts as are necessary in order that the net payment by IBM or a paying agent of the principal of and interest on the Notes to a holder who is not a United States person (as defined below), after deduction for any present or future tax, assessment or other governmental charge of the United States or a political subdivision or taxing authority of or in the United States, imposed by withholding with respect to the payment, will not be less than the amount provided in the Notes to be then due and payable; provided, however, that the foregoing obligation to pay additional amounts shall not apply:

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        The Notes are subject in all cases to any tax, fiscal or other law or regulation or administrative or judicial interpretation applicable to the Notes. Except as specifically provided under this heading "—Payments of Additional Amounts" and under the heading "—Redemption for Tax Reasons," IBM shall not be required to make any payment with respect to any tax, assessment or other governmental charge imposed by any government or a political subdivision or taxing authority of, or in any government or political subdivision.

        As used under this heading "—Payments of Additional Amounts" and under the heading "—Redemption for Tax Reasons", the term "United States" means the United States of America (including the states and the District of Columbia) and its territories, possessions and other areas subject to its jurisdiction, and the term "United States person" means any individual who is a citizen or resident of the United States, a corporation, partnership or other entity created or organized in or under the laws of the United States, any state of the United States or the District of Columbia (other than a partnership that is not treated as a United States person under any applicable Treasury regulations), or any estate or trust the income of which is subject to United States federal income taxation regardless of its source.

Redemption for Tax Reasons

        If, as a result of any change in, or amendment to, the laws (or any regulations or rulings promulgated under the laws) of the United States (or any political subdivision or taxing authority of or in the United States), or any change in, or amendments to, an official position regarding the application or interpretation of such laws, regulations or rulings, which change or amendment is

S-8


announced or becomes effective on or after the date of this prospectus supplement, IBM becomes, or based upon a written opinion of independent counsel selected by IBM, will become obligated to pay additional amounts as described herein under the heading "—Payments of Additional Amounts" with respect to the Notes, then IBM may at its option redeem, in whole, but not in part, the Notes on not less than 30 nor more than 60 days prior notice, at a redemption price equal to 100% of their principal amount, together with interest accrued but unpaid on those Notes to the date fixed for redemption.

Book-Entry System

        Notes which are offered and sold outside the United States (the "international Notes") will be represented by beneficial interests in a fully registered permanent global note (the "international global note") without interest coupons attached, which will be registered in the name of, and shall be deposited on or about November 13, 2006 with a common depositary for, and in respect of interests held through, Euroclear Bank, S.A./N.V., as operator of the Euroclear System ("Euroclear"), and Clearstream Banking, societe anonyme ("Clearstream").

        Notes which are offered and sold in the United States (the "DTC Notes" and, together with the international Notes, the "Notes") will be represented by beneficial interests in a fully registered permanent global Note (the "DTC global Note" and, together with the international global Note, the "global Notes"), without interest coupons attached, which will be deposited on or about November 13, 2006 with The Bank of New York, as custodian for, and registered in the name of Cede & Co., as nominee for, The Depositary Trust Company.

        Together, the Notes represented by the global Notes will equal the aggregate principal amount of the Notes outstanding at any time. The amount of Notes represented by each of the DTC global Note and the international global Note is evidenced by the register maintained for that purpose by the registrar. Beneficial interests in the global Notes will be shown on, and transfers thereof will be affected only through, records maintained by DTC, Euroclear and Clearstream and their participants. Except as described herein, individual registered certificates will not be issued in exchange for beneficial interests in the global Notes.

        A holder of DTC Notes will receive all payments under the DTC Notes in U.S. dollars, unless
such holder makes an election as described herein for payment in euro. The amount payable in U.S. dollars will be equal to the amount of euro otherwise payable exchanged into U.S. dollars at the euro/U.S.$ rate of exchange prevailing two Business Days prior to the relevant payment date.
See "—Issuance in Euro" herein.

        Euroclear advises that it was created in 1968 to hold securities for its participants ("Euroclear Participants") and to clear and settle transactions between Euroclear participants through simultaneous electronic book-entry delivery against payment, thereby eliminating the need for physical movement of certificates and any risk from lack of simultaneous transfers of securities and cash. Euroclear is operated by Euroclear Bank (the "Euroclear Operator"). Euroclear participants include banks (including central banks), securities brokers and dealers and other professional financial intermediaries and may include the Underwriters. Indirect access to Euroclear is also available to other firms that clear through or maintain a custodial relationship with a Euroclear participant, either directly or indirectly.

        Securities clearance accounts and cash accounts with the Euroclear Operator are governed by the Terms and Conditions Governing Use of Euroclear and the related Operating Procedures of the Euroclear System, and applicable Belgian law (collectively, the "Terms and Conditions"). The Terms and Conditions govern transfers of securities and cash within Euroclear, withdrawals of securities and cash from Euroclear, and receipts of payments with respect to securities in Euroclear. All securities in Euroclear are held on a fungible basis without attribution of specific certificates to specific securities clearance accounts. The Euroclear Operator acts under the Terms and Conditions only on behalf of

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Euroclear participants, and has no record of or relationship with persons holding through Euroclear participants.

        Distributions with respect to Notes held beneficially through Euroclear will be credited to the cash accounts of Euroclear participants in accordance with the Terms and Conditions, to the extent received by the U.S. Depositary for Euroclear.

        Clearstream holds securities for its customers and facilitates the clearance and settlement of securities transactions between Clearstream customers through electronic book-entry changes in accounts of Clearstream customers, thereby eliminating the need for physical movement of certificates. Transactions may be settled by Clearstream in any of 36 currencies, including United States Dollars. Clearstream provides to its customers, among other things, services for safekeeping, administration, clearance and settlement of internationally traded securities and securities lending and borrowing. Clearstream also deals with domestic securities markets in over 30 countries through established depository and custodial relationships. Clearstream is registered as a bank in Luxembourg, and as such is subject to regulation by the Commission de Surveillance du Secteur Financier, "CSSF", which supervises Luxembourg banks. Clearstream's customers are world-wide financial institutions including underwriters, securities brokers and dealers, banks, trust companies and clearing corporations. Clearstream's U.S. customers are limited to securities brokers and dealers, and banks. Currently, Clearstream has approximately 2,000 customers located in over 80 countries, including all major European countries, Canada, and the United States. Indirect access to Clearstream is available to other institutions that clear through or maintain a custodial relationship with an account holder of Clearstream. Clearstream has established an electronic bridge with the Euroclear Operator to facilitate settlement of trades between Clearstream and Euroclear.

        Distributions with respect to the Notes held beneficially through Clearstream will be credited to cash accounts of Clearstream participants in accordance with its rules and procedures, to the extent received by the U.S. Depositary for Clearstream.

        Individual certificates in respect of Notes will not be issued in exchange for the Global Notes, except in very limited circumstances. If Euroclear, Clearstream or DTC notifies us that it is unwilling or unable to continue as a clearing system in connection with a Global Note or, in the case of DTC only, DTC ceases to be a clearing agency registered under the Exchange Act, and in each case we do not appoint a successor clearing system within 90 days after receiving such notice from Euroclear, Clearstream or DTC or on becoming aware that DTC is no longer so registered, we will issue or cause to be issued individual certificates in registered form on registration of transfer of, or in exchange for, book-entry interests in the Notes represented by such Global Notes upon delivery of such Global Notes for cancellation.

        If individual certificates are issued, an owner of a beneficial interest in the Global Notes will be entitled to physical delivery in definitive form of Notes represented by the Global Notes equal in principal amount to its beneficial interest and to have those Notes registered in its name. Notes issued in definitive form will be issued as registered Notes in denominations of €50,000 and multiples of €50,000 in addition thereto. You may transfer the definitive Notes by presenting them for registration to the registrar at its New York office. Notes presented for registration must be duly endorsed by you or your attorney duly authorized in writing, or accompanied by a written instrument or instruments of transfer in form satisfactory to us or the trustee duly executed by you or your attorney duly authorized in writing. We may require you to pay a sum sufficient to cover any tax or other governmental charge that may be imposed in connection with any exchange or registration of transfer of definitive Notes.

        In the case of a transfer of part of a holding of Notes represented by one certificate, a new certificate shall be issued to the transferee in respect of the part transferred and a further new certificate in respect of the balance of the holding not transferred shall be issued to the transferor. Any new certificates shall be obtained at the specified office of the registrar within three business days of

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receipt by the registrar. For the purposes of this paragraph, "business day" means a day, other than a Saturday or Sunday, on which banks are open for business in the place of the specified office of the registrar.

        If IBM issues definitive Notes, IBM will do so at the office of The Bank of New York, the paying agent and registrar for the Notes, including any successor paying agent and registrar for the notes, currently located at 4 New York Plaza, New York, New York 10004.

        We may pay interest on definitive Notes, other than interest at maturity or upon redemption, by mailing a check to the address of the person entitled to the interest as it appears on the security register at the close of business on the record date corresponding to the relevant interest payment date.

        Notwithstanding the foregoing, the common depositary, as holder of the Notes, may require the paying agent to make payments of interest, other than interest due at maturity or upon redemption, by wire transfer of immediately available funds into an account maintained in euro by the common depositary, by sending appropriate wire transfer instructions. The paying agent must receive these instructions not less than ten days prior to the applicable interest payment date.

        The paying agent will pay the principal and interest payable at maturity or upon redemption by wire transfer of immediately available funds against presentation of a Note at the office of the paying agent.

        Title to book-entry interests in the Notes will pass by book-entry registration of the transfer within the records of Euroclear, Clearstream or DTC, as the case may be, in accordance with their respective procedures. Book-entry interests in the Notes may be transferred within Euroclear and within Clearstream and between Euroclear and Clearstream in accordance with procedures established for these purposes by Euroclear and Clearstream. Book-entry interests in the Notes may be transferred within DTC in accordance with procedures established for this purpose by DTC. Transfers of book-entry interests in the Notes between Euroclear and Clearstream and DTC may be effected in accordance with procedures established for this purpose by Euroclear, Clearstream, Luxembourg and DTC.

Euroclear, Clearstream and DTC Arrangements

        So long as DTC or its nominee or Euroclear, Clearstream or the nominee of their common depositary is the registered holder of the global Notes, DTC, Euroclear, Clearstream or such nominee, as the case may be, will be considered the sole owner or holder of the Notes represented by such global Notes for all purposes under the Senior Indenture and the Notes. Payments of principal, interest and additional amounts, if any, in respect of the global Notes will be made to DTC, Euroclear, Clearstream or such nominee, as the case may be, as the registered holder thereof. None of IBM, any agent or any underwriter or any affiliate of any of the above or any person by whom any of the above is controlled (as such term is defined in the United States Securities Act of 1933, as amended), have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in the global Notes or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

        Distributions with respect to book-entry interests in the Notes held through Euroclear or Clearstream will be credited, to the extent received by Euroclear or Clearstream from the paying agent, to the cash accounts of Euroclear or Clearstream customers in accordance with the relevant system's rules and procedures.

        Holders of book-entry interests in the Notes through DTC will receive, to the extent received by DTC from the paying agent, all distributions with respect to book-entry interests in the Notes from the paying agent through DTC. Distributions in the United States will be subject to relevant U.S. tax laws and regulations.

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        Interest on the Notes (other than interest on redemption) will be paid to the holder shown on the register on the applicable record date. Trading between the DTC global Note and the international global Note will therefore be net of accrued interest from the record date to the relevant interest payment date.

        Because DTC, Euroclear and Clearstream can only act on behalf of participants, who in turn act on behalf of indirect participants, the ability of a person having an interest in the global Notes to pledge such interest to persons or entities which do not participate in the relevant clearing system, or otherwise take actions in respect of such interest, may be affected by the lack of a physical certificate in respect of such interest.

        The holdings of book-entry interests in the Notes through Euroclear, Clearstream and DTC will be reflected in the book-entry accounts of each such institution. As necessary, the registrar will adjust the amounts of the Notes on the register for the accounts of (i) the common depositary for Euroclear and Clearstream and (ii) Cede & Co. to reflect the amounts of Notes held through Euroclear and Clearstream, and DTC, respectively.

        Beneficial ownership of Notes will be held through financial institutions as direct and indirect participants in Euroclear, Clearstream and DTC. Interests in the global Notes will be in uncertificated book-entry form.

Secondary Market Trading in Relation to Registered Global Notes

        Secondary market sales of book-entry interests in the Notes held through Euroclear or Clearstream to purchasers of book-entry interests in the international Notes through Euroclear or Clearstream will be conducted in accordance with the normal rules and operating procedures of Euroclear and Clearstream and will be settled using the procedures applicable to conventional Eurobonds.

        Secondary market sales of book-entry interests in the DTC Notes between DTC participants will occur in the ordinary way in accordance with DTC rules and will be settled using the procedures applicable to United States corporate debt obligations if payment is effected in U.S. dollars, or free of payment if payment is not effected in U.S. dollars. Where payment is not effected in U.S. dollars, separate payment arrangements outside DTC are required to be made between the DTC participants.

        When book-entry interests in Notes are to be transferred from the account of a DTC participant holding a beneficial interest in a DTC global Note to the account of a Euroclear or Clearstream account holder wishing to purchase a beneficial interest in an international global Note, the DTC participant will deliver instructions for delivery to the relevant Euroclear or Clearstream accountholder to DTC by 12:00 noon, New York City time, on the settlement date. Separate payment arrangements are required to be made between the DTC participant and the relevant Euroclear or Clearstream accountholder. On the settlement date, the custodian will instruct the registrar to (i) decrease the amount of Notes registered in the name of Cede & Co. and evidenced by the DTC global Note and (ii) increase the amount of Notes registered in the name of the nominee of the common depositary for Euroclear and Clearstream and evidenced by the international global Note. Book-entry interests will be delivered free of payment to Euroclear or Clearstream, as the case may be, for credit to the relevant accountholder on the first business day following the settlement date but for value on the settlement date.

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        When book-entry interests in the Notes are to be transferred from the account of a Euroclear or Clearstream accountholder to the account of a DTC participant wishing to purchase a beneficial interest in the DTC global Note, the Euroclear or Clearstream participant must send to Euroclear or Clearstream delivery free of payment instructions by 7:45 p.m., Luxembourg/Brussels time as the case may be, one business day prior to the settlement date. Euroclear or Clearstream, as the case may be, will in turn transmit appropriate instructions to the common depositary for Euroclear and Clearstream and the registrar to arrange delivery to the DTC participant on the settlement date. Separate payment arrangements are required to be made between the DTC participant and the relevant Euroclear and Clearstream accountholder, as the case may be.

        On the settlement date, the common depositary for Euroclear and Clearstream will (a) transmit appropriate instructions to the custodian who will in turn deliver such book-entry interests in the Notes free of payment to the relevant account of the DTC participant and (b) instruct the registrar to (i) decrease the amount of the Notes registered in the name of the nominee of the common depositary for Euroclear and Clearstream and evidenced by the international global Notes and (ii) increase the amount of Notes registered in the name of Cede & Co. and evidenced by the DTC global Note.

        Although the foregoing sets out the procedures of Euroclear, Clearstream and DTC in order to facilitate the transfers of interests in the Notes among participants of DTC, Clearstream and Euroclear, none of Euroclear, Clearstream or DTC is under any obligation to perform or continue to perform such procedures, and such procedures may be discontinued at any time. Neither IBM, the registrar, the Trustee, any paying agent, any underwriter or any affiliate of any of the above, or any person by whom any of the above is controlled for the purposes of the United States Securities Act of 1933, as amended, will have any responsibility for the performance by DTC, Euroclear and Clearstream or their respective direct or indirect participants or accountholders of their respective obligations under the rules and procedures governing their operations or for the sufficiency for any purpose of the arrangements described above.


UNITED STATES TAXATION

General

        This section summarizes the material U.S. tax consequences to holders of Notes. It represents the views of our tax counsel, Cravath, Swaine & Moore LLP. However, the discussion is limited in the following ways:

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        This summary is based on the Code, administrative pronouncements, judicial decisions and final, temporary and proposed Treasury Regulations, changes to any of which subsequent to the date of this Prospectus Supplement may affect the tax consequences described herein. If you are considering buying Notes, we suggest that you consult your tax advisor about the tax consequences of holding the Notes in your particular situation.

Tax Consequences to U.S. Holders

        This section applies to you if you are a "U.S. Holder". A "U.S. Holder" is:

        If a partnership holds Notes, the tax treatment of a partner will generally depend upon the status of the partner and upon the activities of the partnership. If you are a partner of a partnership holding Notes, we suggest that you consult your tax advisor.

Interest

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Sale or Retirement of Notes

        On the sale or retirement of your Note:

Sale of Euro

Foreign Currency Loss

        In general, any foreign currency loss claimed by you will be treated as a "reportable transaction" for U.S. federal income tax purposes to the extent that the amount of the loss equals or exceeds certain threshold amounts ($50,000 in the case of individuals or trusts, whether or not the loss flows through from an S corporation or partnership, and $10 million in the case of corporate taxpayers). You should

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consult your own tax advisors concerning the application of the reportable transaction regulations to your investment in the Notes, including any requirement to file IRS Form 8886.

Information Reporting and Backup Withholding

        Under U.S. federal tax rules concerning information reporting to the IRS:

Tax Consequences to Non-U.S. Holders

        This section applies to you if you are a "Non-U.S. Holder." A "Non-U.S. Holder" is:

Withholding Taxes

        Generally, payments of principal and interest on the Notes will not be subject to U.S. withholding taxes.

        However, for the exemption from withholding taxes on interest to apply to you, you must meet one of the following requirements:

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        Even if you meet one of the above requirements, interest paid to you will be subject to withholding tax under any of the following circumstances:

        We suggest that you consult your tax advisor about the specific methods for satisfying these requirements.

Sale or Retirement of Notes

        If you sell a Note or it is redeemed, you will not be subject to U.S. federal income tax on any gain unless one of the following applies:


U.S. Trade or Business

        If you hold your Note in connection with a trade or business that you are conducting in the United States:

Estate Taxes

        If you are an individual, your Notes will not be subject to U.S. estate tax when you die. However, this rule only applies if, at your death, payments on the Notes were not subject to U.S. federal witholding tax and not connected to a trade or business that you were conducting in the United States.

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Information Reporting and Backup Withholding

        U.S. federal income tax rules concerning information reporting and backup withholding are described above. These rules apply to Non-U.S. Holders as follows:

European Union Tax Reporting and Withholding

        Directive 2003/48/EC (the "Directive") of the Council of the European Union, relating to the taxation of savings income, became effective on July 1, 2005. Under the directive, if a paying agent for interest on a debt claim is resident in one member state of the European Union and an individual who is the beneficial owner of the interest is a resident of another member state, then the former member state is required to provide information (including the identity of the recipient) to authorities of the latter member state. "Paying agent" is defined broadly for this purpose and generally includes any agent of either the payor or payee. Belgium, Luxembourg, and Austria have opted instead to withhold tax on the interest during a transitional period (initially at a rate of 15% but rising in steps to 35% after six years), subject to the ability of the individual to avoid withholding taxes through voluntary disclosure of the investment to the individual's member state. In addition, certain non-members of the European Union (Switzerland, Liechtenstein, Andorra, Monaco, and San Marino), as well as dependent and associated territories of the United Kingdom and the Netherlands, have adopted equivalent measures effective on the same date, including the option to apply withholding taxes as described above.

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UNDERWRITING

        BNP Paribas Securities Corp., Deutsche Bank AG, London Branch and UBS Limited are acting as joint bookrunning managers of the offering, and as representatives of the underwriters named below.

        Subject to terms and conditions stated in the underwriting agreement dated the date of this prospectus supplement, each underwriter named below has severally agreed to purchase, and IBM has agreed to sell to that underwriter, the principal amount of Notes set forth opposite the underwriter's name.


Underwriter
 
Principal Amount
of Notes
BNP Paribas Securities Corp.   €180,000,000
Deutsche Bank AG, London Branch   180,000,000
UBS Limited   180,000,000
Barclays Bank PLC   12,000,000
Goldman Sachs International   12,000,000
J.P. Morgan Securities Ltd.   12,000,000
Morgan Stanley & Co. International Limited   12,000,000
Santander Investment Securities Inc.   12,000,000
   
  Total   €600,000,000
   

        The underwriting agreement provides that the obligation of the several underwriters to pay for and accept delivery of the Notes is subject to the approval of certain legal matters by their counsel and to certain other conditions. The underwriters are obligated to take and pay for all of the Notes if any are taken.

        IBM has been advised by the underwriters that the underwriters propose to offer some of the Notes directly to the public at the public offering price set forth on the cover page of this prospectus supplement and some of the Notes to dealers at the public offering price less a concession not to exceed 0.125% of the principal amount of the Notes. Any underwriter may allow, and such dealers may reallow, a concession not in excess of 0.100% of the principal amount per Note to certain other dealers. After the initial offering of the Notes to the public, the representatives may change the public offering price and concessions.

        The following table shows the underwriting discounts and commission that IBM is to pay to the underwriters in connection with this offering (expressed as a percentage of the principal amount of the notes).


 
 
Paid by IBM
 
Per Note   0.225 %

        The Notes are a new issue of securities with no established trading market. The underwriters have informed IBM that they intend to make a market in the Notes but are under no obligation to do so and such market making may be terminated at any time without notice. IBM intends to apply to list the Notes on the New York Stock Exchange. It is not possible to predict whether the application will be approved for listing or, if approved, whether the application will be approved prior to the settlement date. Settlement of the Notes is not conditional on obtaining the listing, and we are not required to maintain the listing.

        In connection with the offering, Deutsche Bank AG, London Branch, on behalf of the underwriters, may purchase and sell Notes in the open market. These transactions may include over-allotment, syndicate covering transactions and stabilizing transactions. Over-allotment involves syndicate sales of Notes in excess of the principal amount of Notes to be purchased by the underwriters in the offering, which creates a syndicate short position. Syndicate covering transactions involve purchases of the Notes in the open market after the distribution has been completed in order to cover syndicate

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short positions. Stabilizing transactions consist of certain bids or purchases of Notes made for the purpose of preventing or retarding a decline in the market price of the Notes while the offering is in progress.

        The underwriters also may impose a penalty bid. Penalty bids permit the underwriters to reclaim a selling concession from a syndicate member when Deutsche Bank AG, London Branch, in covering syndicate short positions or making stabilizing purchases, repurchases Notes originally sold by that syndicate member.

        Any of these activities may have the effect of preventing or retarding a decline in the market price of the Notes. They may also cause the price of the Notes to be higher than the price that otherwise would exist in the open market in the absence of these transactions. The underwriters may conduct these transactions in the over-the-counter market or otherwise. If the underwriters commence any of these transactions, they may discontinue them at any time.

        The underwriters and certain of their affiliates and associates may engage in transactions with, and/or perform services, including investment banking and general financing and banking services, for, IBM and its subsidiaries in the ordinary course of business.

        IBM has agreed to indemnify the underwriters against certain liabilites, including civil liabilities under the Securities Act of 1933, or contribute to payments which the underwriters may be required to make in respect thereof.

        Expenses payable by IBM are estimated at $325,000. The underwriters have agreed to reimburse IBM for certain of these expenses.

        IBM will deliver the Notes to the underwriters at the closing of this offering when the underwriters pay IBM the purchase price of the Notes. The underwriting agreement provides that the closing will occur on November 13, 2006, which is five business days after the date of this prospectus supplement. Rule 15c6-1 under the Securities Exchange Act of 1934 generally requires that securities trades in the secondary market settle in three business days, unless the parties to a trade expressly agree otherwise.


OFFERING RESTRICTIONS

        The Notes are offered for sale in the United States and in jurisdictions outside the United States, subject to applicable law.

        Each of the underwriters has agreed that it will not offer, sell, or deliver any of the Notes, directly or indirectly, or distribute this prospectus supplement or prospectus or any other offering material relating to the Notes, in or from any jurisdiction except under circumstances that will, to the best of the underwriters' knowledge and belief, result in compliance with the applicable laws and regulations and which will not impose any obligations on IBM except as set forth in the underwriting agreement.

        Noteholders may be required to pay stamp taxes and other charges in accordance with the laws and practices of the country in which the Notes were purchased. These taxes and charges are in addition to the issue price set forth on the cover page.

European Economic Area

        In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a Relevant Member State), each underwriter has represented and agreed that with effect from and including the date on which the Prospectus Directive is implemented in that Relevant Member State (the Relevant Implementation Date) it has not made and will not make an offer of Notes to the public in that Relevant Member State prior to the publication of a prospectus in relation to the Notes which has been approved by the competent authority in that Relevant Member State or, where appropriate, approved in another Relevant Member State and notified to the

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competent authority in the Relevant Member State, all in accordance with the Prospectus Directive, except that it may, with effect from and including the Relevant Implementation Date, make an offer of Notes to the public in that Relevant Member State at any time:

        For the purposes of this provision, the expression an "offer of Notes to the public" in relation to any notes in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the Notes to be offered so as to enable an investor to decide to purchase or subscribe the Notes, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State and the expression Prospectus Directive means Directive 2003/71/EC and includes any relevant implementing measure in each Relevant Member State.

United Kingdom

        Each underwriter has represented and agreed that it and each of its affiliates:

The Republic of Italy

        Each underwriter represents and agrees that it has not offered, sold or delivered, will not offer, sell or deliver, has not distributed and will not distribute and has not made and will not make available in Italy any Notes, the prospectus nor any other offering material relating to the Notes other than:

        Any offer, sale or delivery of the Notes or distribution of copies of the prospectus or any other document relating to the Notes in Italy under (a) or (b) above must be:

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Japan

        The Notes have not been and will not be registered under the Securities and Exchange Law of Japan (the "SEL") and each of the underwriters and each of its affiliates has represented and agreed that it has not offered or sold, and it will not offer or sell, directly or indirectly, any of the Notes in or to residents of Japan or to any persons for reoffering or resale, directly or indirectly, in Japan or to any resident of Japan, except pursuant to an exemption from the registration requirements of the SEL available thereunder and otherwise in compliance with the SEL and the other relevant laws, regulations and guidelines of Japan.

Hong Kong

        The Notes may not be offered or sold by means of any document other than (i) in circumstances which do not constitute an offer to the public within the meaning of the Companies Ordinance (Cap.32, Laws of Hong Kong), or (ii) to "professional investors" within the meaning of the Securities and Futures Ordinance (Cap.571, Laws of Hong Kong) and any rules made thereunder, or (iii) in other circumstances which do not result in the document being a "prospectus" within the meaning of the Companies Ordinance (Cap.32, Laws of Hong Kong), and no advertisement, invitation or document relating to the Notes may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the laws of Hong Kong) other than with respect to Notes which are or are intended to be disposed of only to persons outside Hong Kong or only to "professional investors" within the meaning of the Securities and Futures Ordinance (Cap.571, Laws of Hong Kong) and any rules made thereunder.


LEGAL OPINIONS

        The validity of the Notes offered hereby will be passed upon for IBM by Stuart S. Moskowitz, Senior Counsel of IBM, and for the underwriters by Davis Polk & Wardwell, New York, New York. Mr. Moskowitz, together with members of his family, owns, has options to purchase and has other interests in shares of common stock of IBM. Davis Polk & Wardwell provides legal services to IBM from time to time.

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EXPERTS

        The audited financial statements incorporated in the accompanying Prospectus by reference to IBM's Current Report on Form 8-K dated June 13, 2006, and the financial statement schedule and management's assessment of the effectiveness of internal control over financial reporting (which is included in Management's Report on Internal Control over Financial Reporting) incorporated in the accompanying Prospectus by reference to the Annual Report on Form 10-K of IBM for the year ended December 31, 2005, except as they relate to the financial statements of IBM's Business Consulting Services Reporting Unit for the years ended December 31, 2004 and 2003, have been so incorporated in reliance on the reports of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

        The statements of assets and liabilities and statements of revenues and expenses of the Business Consulting Services Reporting Unit of IBM as of December 31, 2004 and for the years ended December 31, 2004 and 2003 have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their report thereon, appearing in IBM's Current Report on Form 8-K dated June 13, 2006 and incorporated herein by reference.

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PROSPECTUS

INTERNATIONAL BUSINESS MACHINES CORPORATION

New Orchard Road
Armonk, New York 10504
(914) 499-1900

$12,107,437,190
DEBT SECURITIES
PREFERRED STOCK
DEPOSITARY SHARES
CAPITAL STOCK
WARRANTS

WE WILL PROVIDE SPECIFIC TERMS OF THESE SECURITIES
IN SUPPLEMENTS TO THIS PROSPECTUS.

YOU SHOULD READ THIS PROSPECTUS AND ANY SUPPLEMENT CAREFULLY
BEFORE YOU INVEST.

        These securities have not been approved by the Securities and Exchange Commission or any state securities commission, nor have these organizations determined that this prospectus is accurate or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is June 20, 2000.

TABLE OF CONTENTS


 
 
Page
Summary   3
Ratio of Earnings to Fixed Charges and Earnings to Combined Fixed Charges and Preferred Stock Dividends   4
Where You Can find More Information   5
Description of The Company   6
Use of Proceeds   6
Description of The Debt Securities   6
Description of the Preferred Stock   18
Description of the Depositary Shares   19
Description of the Capital Stock   22
Description of the Warrants   22
Plan of Distribution   24
Legal Opinions   24
Experts   24

SUMMARY

        This summary highlights selected information from this document and may not contain all of the information that is important to you. To understand the terms of our securities, you should carefully read this document with the attached prospectus supplement. Together these documents will give the specific terms of the securities we are offering. You should also read the documents we have incorporated by reference into this prospectus for information on us and our financial statements. Certain capitalized terms used in this summary are defined elsewhere in this prospectus.

The Securities We May Offer

        This prospectus is part of a registration statement (No. 333-37034) that we filed with the SEC utilizing a "shelf" registration process. Under this shelf process, we may offer from time to time up to $12,107,437,190 of any of the following securities, either separately or in units: Debt, Preferred Stock, Depositary Shares, Capital Stock and Warrants. This prospectus provides you with a general description of the securities we may offer. Each time we offer securities, we will provide you with a prospectus supplement that will describe the specific amounts, prices and terms of the securities being offered. The prospectus supplement may also add, update or change information contained in this prospectus.

Debt Securities

        We may offer unsecured general obligations of our company, which may be senior or subordinate. The senior debt securities and the subordinated debt securities are together referred to in this prospectus as the "debt securities". The senior debt securities will have the same rank as all of our other unsecured, unsubordinated debt. The subordinated debt securities will be entitled to payment only after payment on our senior indebtedness. Senior indebtedness includes all indebtedness for money borrowed by us, except indebtedness that is stated to be not superior to, or to have the same rank as, the subordinated debt securities. In addition, the subordinated debt securities will be effectively subordinated to creditors and preferred stockholders of our subsidiaries.

        The senior debt securities will be issued under an indenture between us and The Chase Manhattan Bank, as the trustee. The subordinated debt securities will be issued under an indenture between us and the trustee we name in the prospectus supplement. We have summarized general features of the debt securities from the indentures. We encourage you to read the indentures which are exhibits to the registration statement and our recent periodic and current reports that we file with the SEC.

General Indenture Provisions that Apply to Senior and Subordinated Debt Securities

        Neither indenture limits the amount of debt that we may issue. In addition, neither indenture provides holders any protection should there be a recapitalization or restructuring involving our company.

        The indentures allow us to merge or consolidate with another company, or to sell all or most of our assets to another company. If these events occur, the other company will be required to assume our responsibilities relating to the debt securities, and we will be released from all liabilities and obligations.

        The indentures provide that holders of a majority of the outstanding principal amount of any series of debt securities may vote to change our obligations or your rights concerning that series. However, to change the amount or timing of principal, interest or other payments under the debt securities, every holder in the series must consent.

        We may discharge our obligations under the indenture relating to the senior debt securities by depositing with the trustee sufficient funds or government obligations to pay the senior debt securities when due.

        Events of Default.    Each indenture provides that the following are events of default:

3

        If an event of default occurs under any series of debt securities, the trustee or holders of 25% of the outstanding principal amount of that series may declare the principal amount of the series immediately payable. However, holders of a majority of the principal amount may rescind this action.

General Indenture Provisions that Apply Only to Senior Debt Securities

        The indenture relating to the senior debt securities contains covenants restricting our ability to incur secured indebtedness and enter into sale and leaseback transactions.

General Indenture Provisions that Apply Only to Subordinated Debt Securities

        The subordinated debt securities will be subordinated to all senior indebtedness. In addition, claims of our subsidiaries' creditors and preferred stockholders generally will have priority with respect to the subsidiaries' assets and earnings over the claims of our creditors, including holders of the subordinated debt securities. The subordinated debt securities, therefore, will be effectively subordinated to creditors and preferred stockholders of our subsidiaries.

        The indenture relating to the subordinated debt securities does not provide holders any protection in the event of a highly leveraged transaction.

Preferred Stock and Depositary Shares

        We may issue our preferred stock, par value $0.01 per share, in one or more series. Our Board of Directors will determine the dividend, voting, conversion and other rights of the series being offered and the terms and conditions relating to its offering and sale at the time of the offer and sale. We may also issue fractional shares of preferred stock that will be represented by depositary shares and depositary receipts.

Capital Stock

        We may issue our capital stock, par value $0.20 per share. Holders of capital stock are entitled to receive dividends if and when those dividends are declared by our Board of Directors, subject to rights of preferred stockholders. Each holder of capital stock is entitled to one vote per share. The holders of capital stock have no preemptive rights or cumulative voting rights.

Warrants

        We may issue warrants for the purchase of debt securities, preferred stock or capital stock. We may issue warrants independently or together with other securities.

RATIOS OF EARNINGS TO FIXED CHARGES AND EARNINGS TO COMBINED FIXED CHARGES AND PREFERRED STOCK DIVIDENDS

        The ratio of earnings to fixed charges and the ratio of earnings to combined fixed charges and preferred stock dividends for each of the periods indicated are as follows:

 
   Three Months
Ended
March 31,
   Year Ended December 31,
 
   2000
   1999
   1999
   1998
   1997
   1996
   1995
Ratio of earnings to fixed charges   5.71   5.37   7.0   5.3   5.4   5.3   5.0
Ratio of earnings to combined fixed charges and preferred stock dividends   5.63   5.29   6.9   5.3   5.4   5.3   4.9

        We compute the ratio of earnings to fixed charges by dividing earnings, which includes income before taxes and fixed charges, by fixed charges. This calculation excludes the effects of accounting changes which have been made over time. We compute the ratio of earnings to combined fixed charges and preferred stock dividends by dividing earnings by the sum of fixed charges and dividends on preferred stock.

4


For purposes of calculating this ratio, the preferred stock dividend requirements were assumed to be equal to the pre-tax earnings that would be required to cover such dividend requirements based on our effective income tax rates for the respective periods. "Fixed charges" consist of interest on debt and a portion of rentals determined to be representative of interest.

WHERE YOU CAN FIND MORE INFORMATION

        We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any document we file at the SEC's public reference room in Washington, D.C. Please call the SEC at 1-800-SEC-0330 for further information on their public reference room. Our SEC filings are also available to the public at the SEC's web site at (http://www.sec.gov).

        The SEC allows us to "incorporate by reference" into this prospectus the information we file with it. This means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus, and later information that we file with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings made with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 until our offering is completed:

        We encourage you to read our periodic and current reports. Not only do we think these items are interesting reading, we think these reports provide additional information about our company which prudent investors find important. You may request a copy of these filings at no cost, by writing to or telephoning our transfer agent at the following address:

        You should rely only on the information incorporated by reference or provided in this prospectus or any prospectus supplement. We have not authorized anyone else to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information in this prospectus or any prospectus supplement is accurate as of any date other than the date on the front of the document.

5

DESCRIPTION OF THE COMPANY

        We were originally incorporated in the State of New York on June 16, 1911, as the Computing-Tabulating-Recording Co. (C-T-R). C-T-R was a consolidation of the Computing Scale Co. of America, the Tabulating Machine Co., and The International Time Recording Co. of New York. In 1924, C-T-R adopted the name International Business Machines Corporation, also known more simply as IBM.

        We use advanced information technology to provide customer solutions. We operate primarily in a single industry using several segments that create value by offering a variety of solutions that include, either singularly or in some combination, technologies, systems, products, services, software and financing.

        Organizationally, our major operations comprise three hardware products segments—Technology, Personal Systems and Enterprise Systems; a Global Services segment; a Software segment; a Global Financing segment and an Enterprise Investment segment. The segments are determined based on several factors, including customer base, homogeneity of products, technology and delivery channels.

        We offer our products through our global sales and distribution organization. The sales and distribution organization has both a geographic focus (in the Americas, Europe/Middle East/Africa, and Asia Pacific) and a specialized and global industry focus. In addition, this organization includes a global sales and distribution effort devoted exclusively to small and medium businesses. We also offer our products through a variety of third party distributors and resellers, as well as through our on-line channels.

USE OF PROCEEDS

        Unless we otherwise specify in the applicable prospectus supplement, the net proceeds we receive from the sale of the securities offered by this prospectus and the accompanying prospectus supplement will be used for general corporate purposes. General corporate purposes may include the repayment of debt, investments in or extensions of credit to our subsidiaries, redemption of preferred stock, or the financing of possible acquisitions or business expansion. The net proceeds may be invested temporarily or applied to repay short-term debt until they are used for their stated purpose.

DESCRIPTION OF THE DEBT SECURITIES

        The following description of the terms of the debt securities sets forth general terms that may apply to the debt securities. The particular terms of any debt securities will be described in the prospectus supplement relating to those debt securities.

        The debt securities will be either our senior debt securities or our subordinated debt securities. The senior debt securities will be issued under an indenture dated as of October 1, 1993, as supplemented on December 15, 1995, between us and The Chase Manhattan Bank, as trustee. This indenture is referred to as the "senior indenture". The subordinated debt securities will be issued under an indenture to be entered into between us and the trustee named in a prospectus supplement. This indenture is referred to as the "subordinated indenture". The senior indenture and the subordinated indenture are together called the "indentures".

        The following is a summary of the most important provisions of the indentures. Copies of the entire indentures are exhibits to the registration statement of which this prospectus is a part. Section references below are to the section in the applicable indenture. The referenced sections of the indentures are incorporated by reference. We encourage you to read our indentures.

General

        Neither indenture limits the amount of debt securities that we may issue. Each indenture provides that debt securities may be issued up to the principal amount authorized by us from time to time. The senior debt securities will be unsecured and will have the same rank as all of our other unsecured and unsubordinated debt. The subordinated debt securities will be unsecured and will be subordinated and junior to all senior indebtedness.

6


        The debt securities may be issued in one or more separate series of senior debt securities and/or subordinated debt securities. The prospectus supplement relating to the particular series of debt securities being offered will specify the particular amounts, prices and terms of those debt securities. These terms may include:

        (Sections 202 and 301)

        Unless we otherwise specify in the prospectus supplement:

        Debt securities may bear legends required by United States Federal tax law and regulations. (Section 401)

        If any of the debt securities are sold for any foreign currency or currency unit, or if any payments on the debt securities are payable in any foreign currency or currency unit, the prospectus supplement will contain any restrictions, elections, tax consequences, specific terms and other information relating to the debt securities and the foreign currency or currency unit.

        Some of the debt securities may be issued as original issue discount debt securities. Original issue discount securities bear no interest

7


or bear interest at below-market rates. These are sold at a discount below their stated principal amount. If we issue these securities, the prospectus supplement will describe any special tax, accounting or other information which we think is important.

Exchange, Registration and Transfer

        Debt securities may be transferred or exchanged at the corporate trust office of the security registrar or at any other office or agency which is maintained for these purposes. No service charge will be payable upon the transfer or exchange, except for any applicable tax or governmental charge.

        The designated security registrar in the United States for the senior debt securities is The Chase Manhattan Bank, located at 450 West 33rd Street, New York, New York 10001. The security registrar for the subordinated debt securities will be designated in a prospectus supplement.

        If debt securities are issuable in both registered and bearer form, the bearer securities will be exchangeable for registered securities. If a bearer security with related coupons is surrendered in exchange for a registered security between a record date and the date set for the payment of interest, the bearer security will be surrendered without the coupon relating to that interest payment. That interest payment will be made only to the holder of the coupon when due.

        In the event of any redemption in part of any series of debt securities, we will not be required to:

        (Section 404)

Payment and Paying Agent

        We will pay principal, interest and any premium on fully registered securities in the designated currency or currency unit at the office of the paying agent. Payment of interest on fully registered securities may be made by check mailed to the persons in whose names the debt securities are registered on days specified in the indentures or any prospectus supplement. (Sections 406 and 410)

        We will pay principal, interest and any premium on bearer securities in the designated currency or currency unit at the office of the paying agent or agents outside of the United States. Payments will be made at the offices of the paying agent in the United States only if the designated currency is U.S. dollars and payment outside of the United States is illegal or effectively precluded. (Sections 410 and 1102)

        If any amount payable on any debt security or coupon remains unclaimed at the end of two years after the amount became due and payable, the paying agent will release any unclaimed amounts to us. (Section 1103)

        Our paying agent in the United States for the senior debt securities is The Chase Manhattan Bank, located at 450 West 33rd

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Street, New York, New York 10001. If and when we issue subordinated debt securities, we'll designate the paying agent for those subordinated debt securities in the applicable prospectus supplement.

Global Securities

        The debt securities of a series may be issued in whole or in part in the form of one or more global certificates. Those certificates will be deposited with a depositary that we will identify in a prospectus supplement. Global debt securities may be issued in either registered or bearer form and can be in either temporary or definitive form. All global securities in bearer form will be deposited with a depositary outside of the United States. We will describe the specific terms of the depositary arrangement relating to a series of debt securities in the prospectus supplement.

        Other than for payments, we can treat a person having a beneficial interest in a definitive global security as the holder of the principal amount of outstanding debt securities represented by the global security. For these purposes, we can rely upon a written statement delivered to the trustee by the holder of the definitive global security, or, in the case of a definitive global security in bearer form, by Morgan Guaranty Trust Company of New York, Brussels office, as operator of the Euroclear System, and Clearstream Banking, societe anonyme (Clearstream, Luxembourg). (Section 411)

        Neither we, the trustee nor any of our respective agents will be responsible for any aspect of the records relating to or payments made on account of beneficial ownership interests in a global security or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests. (Section 411)

        Unless we otherwise specify in a prospectus supplement, we anticipate that the following provisions will apply to our depositary arrangements:

Temporary Global Securities

        All or any portion of the debt securities of a series that are issuable in bearer form initially may be represented by one or more temporary global securities, without interest coupons. The temporary global securities will be deposited with a depositary in London for Euroclear and Clearstream for credit to the accounts of the beneficial owners of the debt securities or to such other accounts as they may direct.

        On and after an exchange date provided in the applicable prospectus supplement, each temporary global security will be exchangeable for definitive debt securities in bearer form, registered form, definitive global bearer form or a combination of these, as will be specified in the prospectus supplement.

        No bearer security delivered in exchange for a portion of a temporary global security will be mailed or delivered to any location in the United States. (Sections 402 and 403)

        Interest on a temporary global security will be paid to Euroclear and/or Clearstream for the portion held for its account only after a certificate is delivered to the trustee stating that the portion:

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        The certificate must be based on statements provided by the beneficial owners of interests in the temporary global security. Each of Euroclear and Clearstream will credit the interest received by it to the accounts of the beneficial owners of the debt security, or to other accounts as they may direct. (Section 403)

Definitive Global Securities

        Bearer Securities.    The applicable prospectus supplement will describe the exchange provisions, if any, of debt securities issuable in definitive global bearer form. We will not deliver any bearer securities in exchange for a portion of a definitive global security to any location in the United States. (Section 404)

        U.S. Book-Entry Securities.    Debt securities of a series represented by a definitive global registered security and deposited with or on behalf of a depositary in the United States will be registered in the name of the depositary or its nominee. These securities are referred to as "book-entry securities".

        When a global security is issued and deposited with the depositary, the depositary will credit, on its book-entry registration and transfer system, the respective principal amounts represented by that global security to the accounts of institutions that have accounts with the depositary or its nominee. Institutions that have accounts with the depositary or its nominee are referred to as "participants".

        The accounts to be credited shall be designated by the underwriters or agents for the sale of such book-entry securities or by us, if we offer and sell those securities directly.

        Ownership of book-entry securities are limited to participants or persons that may hold interests through participants. In addition, ownership of these securities will be evidenced only by, and the transfer of that ownership will be effected only through, records maintained by the depositary or its nominee or by participants or persons that hold through other participants.

        So long as the depositary, or its nominee, is the registered owner of a global security, that depositary or nominee will be considered the sole owner or holder of the book-entry securities represented by the global security for all purposes under the indenture. Payments of principal, interest and premium on those securities will be made to the depositary or its nominee as the registered owner or the holder of the global security.

        Owners of book-entry securities:


        The laws of some jurisdictions require that purchasers of securities take physical delivery of the securities in definitive form. These laws impair the ability to purchase or transfer book-entry securities. We must comply with the law.

        We expect that the depositary for book-entry securities of a series will immediately credit participants' accounts with payments received by the depositary or nominee in amounts proportionate to the participants' beneficial interests as shown on the records of such depositary.

        We also expect that payments by participants to owners of beneficial interests in a global security held through the participants will be governed by standing instructions and customary practices, as is now the case with securities held for the accounts of customers in bearer form or registered in "street name". The payments by participants to the owners of beneficial interests will be the responsibility of those participants.

Practical Implications of Holding Debt Securities in Street Name

        Investors who hold debt securities in accounts at banks or brokers will not generally be recognized by us as the legal holders of debt

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securities. Since we recognize as the holder the bank or broker, or the financial institution the bank or broker uses to hold its debt securities, it is the responsibility of these intermediary banks, brokers and other financial institutions to pass along principal, interest and other payments on the debt securities, either because they agree to do so in their agreements with their customers, or because they are legally required to do so. If you hold debt securities in street name, you really ought to check with your own institution to find out:

Satisfaction and Discharge; Defeasance

        We may be discharged from our obligations on the debt securities of any series that have matured or will mature or be redeemed within one year if we deposit with the trustee enough cash to pay all the principal, interest and any premium due to the stated maturity date or redemption date of the debt securities. (Section 501)

        Each indenture contains a provision that permits us to elect:

        To make either of the above elections, we must deposit in trust with the trustee enough money to pay in full the principal, interest and premium on the debt securities. This amount may be made in cash and/or U.S. government obligations, if the debt securities are denominated in U.S. dollars. This amount may be made in cash, and/or foreign government securities if the debt securities are denominated in a foreign currency. As a condition to either of the above elections, we must deliver to the trustee an opinion of counsel that the holders of the debt securities will not recognize income, gain or loss for Federal income tax purposes as a result of the action. (Section 503)

        If either of the above events occur, the holders of the debt securities of the series will not be entitled to the benefits of the indenture, except for registration of transfer and exchange of debt securities and replacement of lost, stolen or mutilated debt securities. (Sections 501 and 503)

Events of Default, Notice and Waiver

        If an event of default for any series of debt securities occurs and continues, the trustee or the holders of at least 25% in principal amount of the debt securities of the series may declare the entire principal amount of all the debt securities of that series to be due and payable immediately.

        The declaration may be annulled and past defaults may be waived by the holders of a majority of the principal amount of the debt securities of that series. However, payment defaults that are not cured may only be waived

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by all holders of the debt securities. (Sections 602 and 613)

        Each indenture defines an event of default in connection with any series of debt securities as one or more of the following events:

        An event of default for one series of debt securities is not necessarily an event of default for any other series of debt securities. (Section 601)

        Each indenture requires the trustee to give the holders of a series of debt securities notice of a default for that series within 90 days unless the default is cured or waived. However, the trustee may withhold this notice if it determines in good faith that it is in the interest of those holders. The trustee may not, however, withhold this notice in the case of a payment default. (Section 702)

        Other than the duty to act with the required standard of care during an event of default, a trustee is not obligated to exercise any of its rights or powers under the indenture at the request or direction of any of the holders of debt securities, unless the holders have offered to the trustee reasonable indemnification. (Section 703)

        Generally, the holders of a majority in principal amount of outstanding debt securities of any series may direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or other power conferred on the trustee. (Section 612)

        Each indenture includes a covenant that we will file annually with the trustee a certificate of no default, or specifying any default that exists. (Section 1106)

        Street name and other indirect holders should consult their banks and brokers for information on their requirements for giving notice or taking other actions upon a default.

Modification of the Indentures

        Together with the trustee, we may modify the indentures without the consent of the holders for limited purposes, including adding to our covenants or events of default, establishing forms or terms of debt securities, curing ambiguities and other purposes which do not adversely affect the holders in any material respect. (Section 1001)

        Together with the trustee, we may also make modifications and amendments to each indenture with the consent of the holders of a majority in principal amount of the outstanding debt securities of all affected series. However, without the consent of each affected holder, no modification may:

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        (Section 1002)

Meetings

        The indentures contain provisions for convening meetings of the holders of debt securities of a series. (Section 1401)

        A meeting may be called at any time by the trustee, upon request by us or upon request by the holders of at least 10% in principal amount of the outstanding debt securities of the series. In each case, notice will be given to the holders of debt securities of the series. (Section 1402)

        Persons holding a majority in principal amount of the outstanding debt securities of a series will constitute a quorum at a meeting. A meeting called by us or the trustee that did not have a quorum may be adjourned for not less than 10 days, and if there is not a quorum at the adjourned meeting, the meeting may be further adjourned for not less than 10 days.

        Generally, any resolution presented at a meeting at which a quorum is present may be adopted by the affirmative vote of the holders of a majority in principal amount of the outstanding debt securities of that series. However, to change the amount or timing of payments under the debt securities, every holder in the series must consent.

        In addition, if the indenture provides that an action may be taken by the holders of a specified percentage in principal amount of outstanding debt securities of a series, that action may be taken at a meeting at which a quorum is present by the affirmative vote of the holders of such specified percentage in principal amount of the outstanding debt securities of that series. Any resolution passed or decision taken at any meeting of holders of debt securities of any series duly held in accordance with an indenture will be binding on all holders of debt securities of that series and the related coupons. (Section 1404)

Notices to Holders

        In most instances, notices to holders of bearer securities will be given by publication at least once in a daily newspaper in The City of New York and in London. Notices may also be published in another city or cities as may be specified in the securities. In addition, notices to holders of bearer securities will be mailed to those persons whose names and addresses were previously filed with the applicable trustee. Notice to holders of registered securities will be given by mail to the addresses of the holders as they appear in the security register. (Section 106)

Title

        Title to any bearer securities and any related coupons will pass by delivery. We, the trustee and any agent of ours or the trustee may treat the holder of any bearer security or related coupon as the absolute owner of that security for all purposes. We may also treat the registered owner of any registered security as the absolute owner of that security for all purposes. (Section 407)

Replacement of Securities and Coupons

        We think it's very important for you to keep your securities safe. If you don't, you'll have to follow these procedures. We'll replace debt securities or coupons that have been mutilated, but you'll have to pay for the replacement, and you'll have to surrender the mutilated debt security or coupon to the security registrar first. Debt securities or coupons that become destroyed, stolen or lost will only be replaced by us, again at your expense, upon your providing evidence of destruction, loss or theft which we and the security registrar think is good. In the case of a destroyed, lost or stolen debt security or coupon, we may also require you, as the holder of the debt security or coupon, to indemnify the security registrar and us before we'll go about issuing any replacement debt security or coupon. (Section 405)

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Governing Law

        The indentures, the debt securities and the coupons will be governed by, and construed under, the laws of the State of New York.

Our Relationship with the Trustee

        We may from time to time maintain lines of credit, and have other customary banking relationships, with the trustee under the senior indenture or the trustee under the subordinated indenture.

Senior Debt Securities

        The senior debt securities will be unsecured and will rank equally with all of our other unsecured and non-subordinated debt.

Covenants in the Senior Indenture

        Covenants are promises.    We must keep our promises or we could be placed in default.

        Limitation on Merger, Consolidation and Certain Sales of Assets.    We may, without the consent of the holders of the debt securities, merge into or consolidate with any other corporation, or convey or transfer all or substantially all of our properties and assets to another person provided that:


        The remaining or acquiring corporation will take over all of our rights and obligations under the indentures. (Section 902)

        Limitation on Secured Indebtedness.    Neither we nor any Restricted Subsidiary will create, assume, incur or guarantee any Secured Indebtedness without securing the senior debt securities equally and ratably with, or prior to, that Secured Indebtedness, unless the sum of the following amounts would not exceed 10% of Consolidated Net Tangible Assets:

        You should note that we don't include in this calculation any leases entered into by a Restricted Subsidiary before the time it became a Restricted Subsidiary. (Section 1104)

        Limitation on Sale and Leaseback Transactions.    Neither we nor any Restricted Subsidiary will enter into any lease longer than three years covering any of our Principal Property or any Restricted Subsidiary that is sold to any other person in connection with that lease unless either:

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        We think it's important for you to be aware that this limitation on sale and leaseback transactions won't apply to any leases that we may enter into relating to newly acquired, improved or constructed property.

        We think it's also important for you to note that the holders of a majority in principal amount of all affected series of outstanding debt securities may waive compliance with each of the above covenants. (Section 1107)

Definitions

        "Secured Indebtedness" means our indebtedness or indebtedness of a Restricted Subsidiary for borrowed money secured by any lien on, or any conditional sale or other title retention agreement covering, any Principal Property or any stock or indebtedness of a Restricted Subsidiary. Excluded from this definition is all indebtedness:

        "Principal Property" means land, land improvements, buildings and associated factory, laboratory and office equipment constituting a manufacturing, development, warehouse, service or office facility owned by or leased to us or a Restricted Subsidiary which is located within the United States and which has an acquisition cost plus capitalized improvements in excess of 0.15% of Consolidated Net Tangible Assets as of the date of such determination. Principal Property does not include:

        "Consolidated Net Tangible Assets" means the total assets of us and our subsidiaries, less current liabilities and intangible assets. We

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include in intangible assets the balance sheet value of:

        We don't include in intangible assets any program products.

        "Restricted Subsidiary" means:

        "Restricted Subsidiary" doesn't include financing subsidiaries and subsidiaries formed or acquired after July 15, 1985 for the purpose of acquiring the stock, business or assets of another person and that have not and do not acquire all or any substantial part of our business or assets or the business or assets of any Restricted Subsidiary. (Section 101 of Senior Indenture)

Subordinated Debt Securities

        The subordinated debt securities will be unsecured. The subordinated debt securities will be subordinate in right of payment to all senior indebtedness. (Section 1501 of Subordinated Indenture)

        In addition, claims of our subsidiaries' creditors and preferred stockholders generally will have priority with respect to the assets and earnings of the subsidiaries over the claims of our creditors, including holders of the subordinated debt securities, even though those obligations may not constitute senior indebtedness. The subordinated debt securities, therefore, will be effectively subordinated to creditors, including trade creditors, and preferred stockholders of our subsidiaries.

        The subordinated indenture defines "senior indebtedness" to mean the principal of, premium, if any, and interest on:

        However, the term "senior indebtedness" will not include:

        There is no limitation on our ability to issue additional senior indebtedness. The senior debt securities constitute senior indebtedness under the subordinated indenture. The subordinated debt securities will rank equally with our other subordinated indebtedness.

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        Under the subordinated indenture, no payment may be made on the subordinated debt securities and no purchase, redemption or retirement of any subordinated debt securities may be made in the event:

        We may, however, pay the subordinated debt securities without regard to the above restriction if the representatives of the holders of the applicable senior indebtedness approve the payment in writing to us and the trustee.

        The representatives of the holders of senior indebtedness may notify us and the trustee in writing of a default which can result in the acceleration of that senior indebtedness' maturity without further notice or the expiration of any grace periods. In this event, we may not pay the subordinated debt securities for 179 days after receipt of that notice. If the holders of senior indebtedness or their representatives have not accelerated the maturity of the senior indebtedness at the end of the 179 day period, we may resume payments on the subordinated debt securities. Not more than one such notice may be given in any consecutive 360-day period, irrespective of the number of defaults with respect to senior indebtedness during that period. (Section 1503 of Subordinated Indenture)

        In the event we pay or distribute our assets to creditors upon a total or partial liquidation, dissolution or reorganization of us or our property, the holders of senior indebtedness will be entitled to receive payment in full of the senior indebtedness before the holders of subordinated debt securities are entitled to receive any payment. Until the senior indebtedness is paid in full, any payment or distribution to which holders of subordinated debt securities would be entitled but for the subordination provisions of the subordinated indenture will be made to holders of the senior indebtedness. (Section 1502 of Subordinated Indenture)

        If a distribution is made to holders of subordinated debt securities that, due to the subordination provisions, should not have been made to them, those holders of subordinated debt securities are required to hold it in trust for the holders of senior indebtedness, and pay it over to them as their interests may appear. (Section 1505 of Subordinated Indenture)

        If payment of the subordinated debt securities is accelerated because of an event of default, either we or the trustee will promptly notify the holders of senior indebtedness or their representatives of the acceleration. We may not pay the subordinated debt securities until five business days after the holders of senior indebtedness or their representatives receive notice of the acceleration. Thereafter, we may pay the subordinated debt securities only if the subordination provisions of the subordinated indenture otherwise permit payment at that time. (Section 1505 of Subordinated Indenture)

        As a result of the subordination provisions contained in the subordinated indenture, in the event of insolvency, our creditors who are holders of senior indebtedness may recover more, ratably, than the holders of subordinated debt securities. In addition, our creditors who are not holders of senior indebtedness may recover less, ratably, than holders of senior indebtedness and may recover more, ratably, than the holders of subordinated indebtedness. It's important to keep this in mind if you decide to hold our subordinated debt securities.

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DESCRIPTION OF THE PREFERRED STOCK

        The following is a description of general terms and provisions of the preferred stock. The particular terms of any series of preferred stock will be described in the applicable prospectus supplement.

        All of the terms of the preferred stock are, or will be, contained in our Certificate of Incorporation and the certificate of amendment relating to each series of the preferred stock, which will be filed with the Securities and Exchange Commission at or before the time we issue a series of the preferred stock.

        We are authorized to issue up to 150,000,000 shares of preferred stock, par value $.01 per share. As of March 31, 2000, 2,546,011 shares of Series A 71/2% Preferred Stock, liquidation preference $100 per share, were outstanding. Subject to limitations prescribed by law, the Board of Directors is authorized at any time to:

        The Board of Directors is authorized to determine, for each series of preferred stock, and the prospectus supplement will set forth with respect to the series the following information:

The preferred stock, when issued, will be fully paid and nonassessable.

Dividends

        Holders of preferred stock will be entitled to receive, when, as and if declared by our Board of Directors, cash dividends at the rates and on the dates as set forth in the prospectus supplement. Generally, no dividends will be declared or paid on any series of preferred stock unless full dividends for all series of preferred stock, including any cumulative dividends still owing, have been or contemporaneously are declared and paid. When those dividends are not paid in full, dividends will be declared pro-rata so that the amount of dividends declared per share on each series of preferred stock will bear to each other series the same ratio that accrued dividends per share for each respective series of preferred stock bear to aggregate accrued dividends for all outstanding shares of preferred stock. In addition, generally, unless all dividends on the preferred stock have been paid, no dividends will be declared or paid on the capital stock and we may not redeem or purchase any capital stock.

        Payment of dividends on any series of preferred stock may be restricted by loan agreements, indentures and other transactions we may enter into.

Convertibility

        No series of preferred stock will be convertible into, or exchangeable for, other securities or property except as set forth in the applicable prospectus supplement.

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Redemption and Sinking Fund

        No series of preferred stock will be redeemable or receive the benefit of a sinking fund except as set forth in the applicable prospectus supplement.

        Shares of preferred stock that we redeem or otherwise reacquire will resume the status of authorized and unissued shares of preferred stock undesignated as to series, and will be available for subsequent issuance. There are no restrictions on repurchase or redemption of the preferred stock while there is any arrearage on sinking fund installments except as may be set forth in a prospectus supplement.

Liquidation

        In the event we voluntarily or involuntarily liquidate, dissolve or wind up our affairs, the holders of each series of preferred stock will be entitled to receive the liquidation preference per share specified in the prospectus supplement, plus any accrued and unpaid dividends. Holders of preferred stock will be entitled to receive these amounts before any distribution is made to the holders of capital stock.

        If the amounts payable to preferred stockholders are not paid in full, the holders of preferred stock will share ratably in any distribution of assets based upon the aggregate liquidation preference for all outstanding shares for each series. After the holders of shares of preferred stock are paid in full, they will have no right or claim to any of our remaining assets.

        Neither the par value nor the liquidation preference is indicative of the price at which the preferred stock will actually trade on or after the date of issuance.

Voting

        Generally, the holders of preferred stock will not be entitled to vote. However, if the equivalent of six quarterly dividends payable on any series of preferred stock is in default, the number of directors constituting our Board of Directors will be increased by two and the holders of such series of preferred stock, voting together as a class with all other series of preferred stock entitled to vote on such election of directors, will be entitled to elect those additional directors. In the event of this type of default, the Board of Directors will call a special meeting for the holders of all affected series within 10 business days of the default for the purpose of electing the additional directors. Alternatively, the holders of record of a majority of the outstanding shares of all affected series who are entitled to participate in the election of directors may elect those additional directors by written consent. If all accumulated dividends on any series of preferred stock have been paid in full, the holders of shares of that series will no longer have the right to vote on directors, the term of office of each director so elected will terminate, and the number of our directors will, without further action, be reduced by two.

        Unless we otherwise specify in a prospectus supplement, the vote of the holders of a majority of the outstanding shares of each series of preferred stock voting together as a class, is required to authorize any amendment, alteration or repeal of our Certificate of Incorporation or any certificate of amendment which would adversely affect the powers, preferences, or special rights of the preferred stock including authorizing any class of stock with superior dividend and liquidation preferences.

No Other Rights

        The shares of a series of preferred stock will not have any preemptive rights, preferences, voting powers or relative, participating, optional or other special rights except as set forth above or in the prospectus supplement, the Certificate of Incorporation or certificate of amendment or as otherwise required by law.

Transfer Agent and Registrar

        We'll designate the transfer agent for each series of preferred stock in the prospectus supplement.

DESCRIPTION OF THE DEPOSITARY SHARES

        We may, at our option, elect to offer fractional shares of preferred stock, rather than full shares of preferred stock. If we do, we will issue to the public receipts for depositary shares,

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and each of these depositary shares will represent a fraction of a share of a particular series of preferred stock. Each owner of a depositary share will be entitled, in proportion to the applicable fractional interest in shares of preferred stock underlying that depositary share, to all rights and preferences of the preferred stock underlying that depositary share. Those rights include dividend, voting, redemption and liquidation rights.

        The shares of preferred stock underlying the depositary shares will be deposited with a depositary under a deposit agreement between us, the depositary and the holders of the depositary receipts evidencing the depositary shares. The depositary will be a bank or trust company selected by us. The depositary will also act as the transfer agent, registrar and dividend disbursing agent for the depositary shares.

        Holders of depositary receipts agree to be bound by the deposit agreement, which requires holders to take certain actions such as filing proof of residence and paying certain charges.

        The following is a summary of the most important terms of the depositary shares. The deposit agreement, our Certificate of Incorporation and the certificate of amendment for the applicable series of preferred stock that are, or will be, filed with the SEC will set forth all of the terms relating to the depositary shares.

Dividends

        The depositary will distribute all cash dividends or other cash distributions received relating to the series of preferred stock underlying the depositary shares, to the record holders of depositary receipts in proportion to the number of depositary shares owned by those holders on the relevant record date. The record date for the depositary shares will be the same date as the record date for the preferred stock.

        In the event of a distribution other than in cash, the depositary will distribute property received by it to the record holders of depositary receipts that are entitled to receive the distribution. However, if the depositary determines that it is not feasible to make the distribution, the depositary may, with our approval, adopt another method for the distribution. The method may include selling the property and distributing the net proceeds to the holders.

Liquidation Preference

        In the event of our voluntary or involuntary liquidation, dissolution or winding up, the holders of each depositary share will be entitled to receive the fraction of the liquidation preference accorded each share of the applicable series of preferred stock, as set forth in the applicable prospectus supplement.

Redemption

        If a series of preferred stock underlying the depositary shares is subject to redemption, the depositary shares will be redeemed from the proceeds received by the depositary resulting from the redemption, in whole or in part, of preferred stock held by the depositary. Whenever we redeem any preferred stock held by the depositary, the depositary will redeem, as of the same redemption date, the number of depositary shares representing the preferred stock so redeemed. The depositary will mail the notice of redemption to the record holders of the depositary receipts promptly upon receiving the notice from us and not less than 35 nor more than 60 days prior to the date fixed for redemption of the preferred stock and the depositary shares.

Voting

        Upon receipt of notice of any meeting at which the holders of preferred stock are entitled to vote, the depositary will mail the information contained in the notice of meeting to the record holders of the depositary receipts underlying the preferred stock. Each record holder of those depositary receipts on the record date will be entitled to instruct the depositary as to the exercise of the voting rights pertaining to the amount of preferred stock underlying that holder's depositary shares. The record date for the depositary shares will be the same date as the record date for the preferred stock. The depositary will try, as far as practicable, to vote the preferred stock underlying the depositary

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shares in a manner consistent with the instructions of the holders of the depositary receipts. We will agree to take all action which may be deemed necessary by the depositary in order to enable the depositary to do so. The depositary will not vote the preferred stock to the extent that it does not receive specific instructions from the holders of depositary receipts.

Withdrawal of Preferred Stock

        Owners of depositary shares are entitled, upon surrender of depositary receipts at the principal office of the depositary and payment of any unpaid amount due the depositary, to receive the number of whole shares of preferred stock underlying the depositary shares. Partial shares of preferred stock will not be issued. These holders of preferred stock will not be entitled to deposit the shares under the deposit agreement or to receive depositary receipts evidencing depositary shares for the preferred stock.

Amendment and Termination of Deposit Agreement

        The form of depositary receipt evidencing the depositary shares and any provision of the deposit agreement may be amended at any time and from time to time by agreement between us and the depositary. However, any amendment which materially and adversely alters the rights of the holders of depositary shares, other than any change in fees, will not be effective unless the amendment has been approved by at least a majority of the depositary shares then outstanding. The deposit agreement may be terminated by us or the depositary only if:

Charges of Depositary

        We'll pay all transfer and other taxes and governmental charges arising solely from the existence of the depositary arrangements. We'll also pay charges of the depositary in connection with the initial deposit of the preferred stock and the initial issuance of the depositary shares, any redemption of the preferred stock and all withdrawals of preferred stock by owners of depositary shares. Holders of depositary receipts will pay transfer, income and other taxes and governmental charges and certain other charges as provided in the deposit agreement. In certain circumstances, the depositary may refuse to transfer depositary shares, withhold dividends and distributions, and sell the depositary shares evidenced by the depositary receipt, if the charges are not paid.

Reports to Holders

        The depositary will forward to the holders of depositary receipts all reports and communications we deliver to the depositary that we are required to furnish to the holders of the preferred stock. In addition, the depositary will make available for inspection by holders of depositary receipts at the principal office of the depositary—and at other places as it thinks is advisable—any reports and communications we deliver to the depositary as the holder of preferred stock.

Liability and Legal Proceedings

        Neither we nor the depositary will be liable if either of us are prevented or delayed by law or any circumstance beyond our control in performing our obligations under the deposit agreement. Our obligations and those of the depositary will be limited to performance in good faith of our duties under the deposit agreement. Neither we nor the depositary will be obligated to prosecute or defend any legal proceeding in respect of any depositary shares or preferred stock unless satisfactory indemnity is furnished. We and the depositary may rely on written advice of counsel or accountants, on information provided by holders of depositary receipts or other persons believed in good faith to be competent to give such information and on

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documents believed to be genuine and to have been signed or presented by the proper persons.

Resignation and Removal of Depositary

        The depositary may resign at any time by delivering a notice to us of its election to do so. We may also remove the depositary at any time. Any such resignation or removal will take effect upon the appointment of a successor depositary and its acceptance of such appointment. The successor depositary must be appointed within 60 days after delivery of the notice for resignation or removal. In addition, the successor depositary must be a bank or trust company having its principal office in the United States of America and must have a combined capital and surplus of at least $150,000,000.

Federal Income Tax Consequences

        Owners of the depositary shares will be treated for Federal income tax purposes as if they were owners of the preferred stock underlying the depositary shares. Accordingly, the owners will be entitled to take into account for Federal income tax purposes income and deductions to which they would be entitled if they were holders of the preferred stock. In addition:

DESCRIPTION OF THE CAPITAL STOCK

        As of the date of this prospectus, we are authorized to issue up to 4,687,500,000 shares of capital stock, $0.20 par value per share. As of March 31, 2000, 1,772,836,653 shares of capital stock were outstanding.

        Dividends.    Holders of capital stock are entitled to receive dividends, in cash, securities, or property, as may from time to time be declared by our Board of Directors, subject to the rights of the holders of the preferred stock.

        Voting.    Each holder of capital stock is entitled to one vote per share on all matters requiring a vote of the stockholders.

        Rights upon Liquidation.    In the event of our voluntary or involuntary liquidation, dissolution, or winding up, the holders of capital stock will be entitled to share equally in our assets available for distribution after payment in full of all debts and after the holders of preferred stock have received their liquidation preferences in full.

        Miscellaneous.    Shares of capital stock are not redeemable and have no subscription, conversion or preemptive rights.

DESCRIPTION OF THE WARRANTS

        We may issue warrants for the purchase of debt securities, preferred stock or capital stock. Warrants may be issued independently or together with our debt securities, preferred stock or capital stock and may be attached to or separate from any offered securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and a bank or trust company, as warrant agent. The warrant agent will act solely as our agent in connection with the warrants and will not have any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants. A copy of the warrant agreement will be filed with the SEC in connection with the offering of warrants.

Debt Warrants

        The prospectus supplement relating to a particular issue of warrants to issue debt securities will describe the terms of those warrants, including the following:

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Stock Warrants

        The prospectus supplement relating to a particular issue of warrants to issue capital stock or preferred stock will describe the terms of the warrants, including the following:

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PLAN OF DISTRIBUTION

        We may sell the securities:

        We'll describe in a prospectus supplement, the particular terms of the offering of the securities, including the following:

        If we use underwriters in the sale, the securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions, including negotiated transactions, either at a fixed public offering price, or at varying prices determined at the time of sale.

        The securities may be either offered to the public through underwriting syndicates represented by managing underwriters or by underwriters without a syndicate. The obligations of the underwriters to purchase securities will be subject to conditions precedent, and the underwriters will be obligated to purchase all the securities of a series if any are purchased. Any initial public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

        Securities may be sold directly by us or through agents designated by us from time to time. Any agent involved in the offer or sale of the securities for which this prospectus is delivered will be named, and any commissions payable by us to that agent will be set forth, in the prospectus supplement. Unless otherwise indicated in the prospectus supplement, any agent will be acting on a best efforts basis for the period of its appointment.

        We may authorize agents or underwriters to solicit offers by certain types of institutions to purchase securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts. These contracts will provide for payment and delivery on a specified date in the future. The conditions to these contracts and the commissions payable for solicitation of such contracts will be set forth in the applicable prospectus supplement.

        Agents and underwriters may be entitled to indemnification by us against civil liabilities arising out of this prospectus, including liabilities under the Securities Act of 1933, or to contribution for payments which the agents or underwriters may be required to make relating to those liabilities. Agents and underwriters may be customers of, engage in transactions with, or perform services for, us in the ordinary course of business.

        Each series of securities will be a new issue of securities with no established trading market. Any underwriter may make a market in the securities, but won't be obligated to do so, and may discontinue any market making at any time without notice. We can't and won't give any assurances as to the liquidity of the trading market for any of our securities.

LEGAL OPINIONS

        The legality of the securities will be passed upon by Mr. David S. Hershberg, our Vice President and Assistant General Counsel. Mr. Hershberg, together with members of his family, owns, has options to purchase and has other interests in shares of our common stock.

EXPERTS

        The consolidated financial statements incorporated in this prospectus by reference to the Annual Report on Form 10-K for the year ended December 31, 1999 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, independent accountants, given on the authority of said firm as experts in auditing and accounting.

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€600,000,000

4% Notes due 2011

GRAPHIC

P R O S P E C T U S      S U P P L E M E N T

November 6, 2006



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TABLE OF CONTENTS
INTERNATIONAL BUSINESS MACHINES CORPORATION
USE OF PROCEEDS
CAPITALIZATION
RATIO OF INCOME FROM CONTINUING OPERATIONS TO FIXED CHARGES
DESCRIPTION OF NOTES
UNITED STATES TAXATION
UNDERWRITING
OFFERING RESTRICTIONS
LEGAL OPINIONS
EXPERTS