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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                           --------------------------

                                  SCHEDULE TO
           TENDER OFFER STATEMENT UNDER SECTION 14(D)(1) OR 13(E)(1)
                     OF THE SECURITIES EXCHANGE ACT OF 1934
                               (AMENDMENT NO. 1)
                           --------------------------

                     CREDIT SUISSE FIRST BOSTON (USA), INC.
                           (NAME OF SUBJECT COMPANY)
                         ------------------------------

                              CREDIT SUISSE GROUP
                          CSFBDIRECT ACQUISITION CORP.
                        CREDIT SUISSE FIRST BOSTON, INC.
    (NAMES OF FILING PERSONS (IDENTIFYING STATUS AS OFFEROR, ISSUER OR OTHER
                                    PERSON))
                         ------------------------------

                     COMMON STOCK OF THE SERIES DESIGNATED
 CREDIT SUISSE FIRST BOSTON (USA), INC. CSFBDIRECT COMMON STOCK, PAR VALUE $.10
                                   PER SHARE
                         TITLE OF CLASS OF SECURITIES)
                         ------------------------------

                                   22541L103
                     (CUSIP NUMBER OF CLASS OF SECURITIES)


                                                       
                  DAVID P. FRICK, ESQ.                                   JOSEPH T. MCLAUGHLIN, ESQ.
                  CREDIT SUISSE GROUP                                 CREDIT SUISSE FIRST BOSTON, INC.
               PARADEPLATZ 8, P.O. BOX 1                                   ELEVEN MADISON AVENUE
              CH-8070 ZURICH, SWITZERLAND                                 NEW YORK, NEW YORK 10010
                     41-1-212-1616                                             (212) 325-2000


(NAME, ADDRESS AND TELEPHONE NUMBER OF PERSONS AUTHORIZED TO RECEIVE NOTICES AND
                  COMMUNICATIONS ON BEHALF OF FILING PERSONS)
                         ------------------------------

                                    COPY TO:
                              CLARE O'BRIEN, ESQ.
                              SHEARMAN & STERLING
                              599 LEXINGTON AVENUE
                            NEW YORK, NEW YORK 10022
                                 (212) 848-4000

                           CALCULATION OF FILING FEE



              TRANSACTION VALUATION*                              AMOUNT OF FILING FEE**
                                                 
                 $110,400,000.00                                        $22,080.00


*   Estimated for purposes of calculating the amount of the filing fee only.
    Calculated by multiplying $6.00, the per share tender offer price, by
    18,400,00, the number of currently outstanding shares of CSFBdirect Common
    Stock sought in the Offer.

**  Calculated as 1/50 of 1% of the transaction value.

/X/  Check the box if any part of the fee is offset as provided by Rule
    0-11(a)(2) and identify the filing with which the offsetting fee was
    previously paid. Identify the previous filing by registration statement
    number, or the Form or Schedule and the date of its filing.


                                                 
Amount Previously Paid: $22,080.00                  Filing Party:Credit Suisse Group,
                                                               Credit Suisse First Boston, Inc.,
                                                               CSFBdirect Acquisition Corp.
Form or Registration No.: Schedule TO               Date Filed: July 24, 2001


Check the box if the filing relates solely to preliminary communications made
before the commencement of a tender offer.  / /

Check the appropriate boxes to designate any transactions to which the statement
relates:

/X/  third-party tender offer subject to Rule 14d-1.

/ /  issuer tender offer subject to Rule 13e-4

/X/  going-private transaction subject to Rule13e-3.

/ /  amendment to Schedule 13D under Rule 13d-2.

    Check the following box if the filing is a final amendment reporting the
results of the tender offer.  / /

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    This Amendment No. 1 (the "Amendment") amends and supplements the Tender
Offer and Schedule 13E-3 Transaction Statement on Schedule TO, filed with the
Securities and Exchange Commission on July 24, 2001 (the "Schedule TO") by
Credit Suisse Group, a corporation organized under the laws of Switzerland
("CSG"), Credit Suisse First Boston, Inc., a Delaware corporation and an
indirect wholly owned subsidiary of CSG ("CSFB"), and CSFBdirect Acquisition
Corp., a Delaware corporation and a wholly owned subsidiary of CSFB
("Purchaser"). The Schedule TO relates to the offer by Purchaser to purchase all
outstanding shares of common stock of the series designated Credit Suisse First
Boston (USA), Inc. CSFBDIRECT Common Stock, par value $0.10 per share (the
"Shares"), of Credit Suisse Boston (USA), Inc., a Delaware corporation (the
"Company"), at a price of $6.00 per Share, net to the seller in cash, upon the
terms and subject to the conditions set forth in the Offer to Purchase dated
July 24, 2001 (the "Offer to Purchase") and in the related Letter of
Transmittal, copies of which are filed as Exhibits (a)(1) and (a)(2) of the
Schedule TO (which, together with the Offer to Purchase and any amendments or
supplements thereto, collectively constitute the "Offer"). Capitalized terms
used and not defined herein shall have the meanings ascribed to such terms in
the Offer to Purchase and the Schedule TO.

    The outside front cover page of the Offer to Purchase, attached as
Exhibit (a)(1) to the Schedule TO, is amended and replaced in its entirety by
the outside front cover page filed herewith as Exhibit (a)(9).

    After due inquiry and to the best of my knowledge and belief, I certify that
the information set forth in this statement is true, complete and correct.

Dated: July 24, 2001


                                                      
                                                       CSFBDIRECT ACQUISITION CORP.

                                                       By:  /s/ NEIL RADEY
                                                            -----------------------------------------
                                                            Name: Neil Radey
                                                            Title: Treasurer


    After due inquiry and to the best of my knowledge and belief, I certify that
the information set forth in this statement is true, complete and correct.

Dated: July 24, 2001


                                                      
                                                       CREDIT SUISSE FIRST BOSTON, INC.

                                                       By:  /s/ ANTHONY F. DADDINO
                                                            -----------------------------------------
                                                            Name: Anthony F. Daddino
                                                            Title: Chief Administrative Officer



    After due inquiry and to the best of my knowledge and belief, I certify that
the information set forth in this statement is true, complete and correct.

Dated: July 24, 2001


                                                      
                                                       CREDIT SUISSE GROUP

                                                       By:  /s/ RICHARD E. THORNBURGH
                                                            -----------------------------------------
                                                            Name: Richard E. Thornburgh
                                                            Title: Attorney-In-Fact

                                                       By:  /s/ NEIL RADEY
                                                            -----------------------------------------
                                                            Name: Neil Radey
                                                            Title: Attorney-In-Fact


                                 EXHIBIT INDEX



     EXHIBIT NO.
---------------------
                     
 (a)(1)                 Offer to Purchase dated July 24, 2001*

 (a)(2)                 Form of Letter of Transmittal.*

 (a)(3)                 Form of Notice of Guaranteed Delivery.*

 (a)(4)                 Form of Letter to Brokers, Dealers, Commercial Banks, Trust
                        Companies and Other Nominees.*

 (a)(5)                 Form of Letter from Brokers, Dealers, Commercial Banks,
                        Trust Companies and Nominees to Clients.*

 (a)(6)                 Form of Guidelines for Certification of Taxpayer
                        Identification Number on Substitute Form W-9.*

 (a)(7)                 Summary Advertisement as published in THE NEW YORK TIMES on
                        July 24, 2001.*

 (a)(8)                 Joint Press Release issued by CSFB and the Company on July
                        11, 200 (incorporated by reference to exhibit 99.1 of the
                        Schedule TO-C filed by CSG, CSFB and Purchaser on July 11,
                        2001).

 (a)(9)                 Revised outside front cover page of the Offer to Purchase
                        filed as Exhibit (a)(1) to the Schedule TO filed by Credit
                        Suisse Group, Credit Suisse First Boston, Inc. and
                        CSFBdirect Acquisition Corp. on July 24, 2001.

 (b)                    None.

 (c)(1)                 Opinion of Lazard Freres & Co. LLC ("Lazard") to the Special
                        Committee of Independent Directors of the Board of Directors
                        of the Company (the "Special Committee") dated July 10, 2001
                        (included as Annex A of the Offer to Purchase filed herewith
                        as Exhibit (a)(1)).*

 (c)(2)                 Materials presented by Lazard to the Special Committee on
                        May 31, 2001.*

 (c)(3)                 Materials presented by Lazard to the Special Committee on
                        July 10, 2001.*

 (d)(1)                 Agreement and Plan of Merger, dated as of July 11, 2001,
                        among CSFB, Purchaser and the Company.*

 (d)(2)                 Credit Suisse Group International Share Plan (incorporated
                        herein by reference to Exhibit 10.6 of the Company's Annual
                        Report on Form 10-K for the year ended December 31, 2000
                        filed with the Securities and Exchange Commission on
                        March 29, 2001).*

 (f)                    Section 262 of the Delaware General Corporation Law
                        (included as Annex B of the Offer to Purchase filed herewith
                        as Exhibit (a)(1)).*

 (g)                    None.

 (h)                    None.


*   Incorporated by reference to the Schedule TO filed by Credit Suisse Group,
    Credit Suisse First Boston, Inc. and CSFBdirect Acquisition Corp. on
    July 24, 2001.