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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


                                   FORM N-1A

     REGISTRATION STATEMENT (NO. 2-56846) UNDER THE SECURITIES ACT OF 1933


                        POST-EFFECTIVE AMENDMENT NO. 82

                                      AND

        REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940


                                AMENDMENT NO. 83


                              VANGUARD INDEX TRUST
        (EXACT NAME OF REGISTRANT AS SPECIFIED IN DECLARATION OF TRUST)

                     P.O. BOX 2600, VALLEY FORGE, PA 19482
                    (ADDRESS OF PRINCIPAL EXECUTIVE OFFICE)

                  REGISTRANT'S TELEPHONE NUMBER (610) 669-1000

                           R. GREGORY BARTON, ESQUIRE
                                  P.O. BOX 876
                             VALLEY FORGE, PA 19482



It is proposed that this filing become effective on December 27, 2001,  pursuant
to Rule  (b)(i)(v) of Rule 485. This  post-effective  amendment is being made to
extend the date of effectiveness for previously filed post-effective  amendments
(Post-Effective Amendment No. 75, 76, 77, 79, and 80).










December 18, 2001




U.S. Securities & Exchange Commission
450 Fifth Street, N.W.
Washington, DC 20549


RE:  VANGUARD INDEX FUNDS (THE TRUST)
     FILE NO.  2-56846
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Commissioners:


Pursuant to Rule 485(b)(i)(v)  under the Securities Act of 1933, as amended,  we
are  submitting  this  filing for the sole  purpose  of  extending  the  pending
effective date of the 75th, 76th, 77th, 79th, and 80th Post-Effective Amendments
to  the  Trust's  Registration  Statement.   Post-Effective   Amendment  No.  75
originally  requested  an  effective  date of August  28,  2001.  Post-Effective
Amendments  No. 76 77, 79, and 80 requested  extension  dates of  September  26,
2001, October 25, 2001, November 23, 2001, and December 21, 2001,  respectively.
It is proposed that this filing become effective on December 27, 2001,  pursuant
to Rule (b)(i)(v) of rule 485. The contents of the Post-Effective  Amendment No.
75, which we filed under Rule 485(a) on June 29, 2001,  are hereby  incorporated
by reference into this letter.

Please  contact me at (610) 503-2398 if you have any questions  concerning  this
amendment or the requested effective date. Thank you.

Sincerely,





Barry A. Mendelson
Principal and Associate Counsel


cc: Christian Sandoe, Esq., U.S. Securities and Exchange Commission




                                   SIGNATURES

Pursuant to the  requirements  of the  Securities Act of 1933 and the Investment
Company  Act of  1940,  the  Registrant  hereby  certifies  that  it  meets  all
requirements for effectiveness of this Registration  Statement  pursuant to Rule
485(b) under the  Securities  Act of 1933 and has duly caused this  Registration
Statement  to be  signed  on its  behalf  by  the  undersigned,  thereunto  duly
authorized, in the Town of Valley Forge and the Commonwealth of Pennsylvania, on
the 18th day of December, 2001.


                                          VANGUARD INDEX FUNDS

                                   BY:_____________(signature)________________

                                    (HEIDI STAM) JOHN J. BRENNAN* CHAIRMAN AND
                                              CHIEF EXECUTIVE OFFICER


     Pursuant  to  the   requirements  of  the  Securities  Act  of  1933,  this
Post-Effective  Amendment to the Registration Statement has been signed below by
the following persons in the capacities and on the date indicated:

SIGNATURE                     TITLE                              DATE
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By:/S/ JOHN J. BRENNAN        President, Chairman, Chief      December 18, 2001
   ---------------------------Executive Officer, and Trustee
       (Heidi Stam)
      John J. Brennan*


By:/S/ JOANN HEFFERNAN HEISEN Trustee                         December 18, 2001
   ---------------------------
       (Heidi Stam)
     JoAnn Heffernan Heisen*


By:/S/ BRUCE K. MACLAURY      Trustee                         December 18, 2001
   ---------------------------
       (Heidi Stam)
      Bruce K. MacLaury*


By:/S/ BURTON G. MALKIEL      Trustee                         December 18, 2001
   ---------------------------
       (Heidi Stam)
       Burton G. Malkiel*


By:/S/ ALFRED M. RANKIN, JR.  Trustee                         December 18, 2001
   ---------------------------
       (Heidi Stam)
     Alfred M. Rankin, Jr.*


By:/S/ JAMES O. WELCH, JR.    Trustee                         December 18, 2001
   ---------------------------
       (Heidi Stam)
     James O. Welch, Jr.*


By:/S/ J. LAWRENCE WILSON     Trustee                         December 18, 2001
   ---------------------------
       (Heidi Stam)
     J. Lawrence Wilson*


By:/S/ THOMAS J. HIGGINS      Treasurer and Principal         December 18, 2001
   ---------------------------
       (Heidi Stam)           Financial Officer and Principal
      Thomas J. Higgins*      Accounting Officer

*By  Power  of  Attorney.  See File  Number  33-32548,  filed on July 24,  2001.
Incorporated by Reference.