[SHIP][VANGUARD]
                                                                   P.O. Box 2600
                                                     Valley Forge, PA 19482-2600

                                                                    610-669-1538
                                                                   Judy_L_Gaines

April 12, 2006


Christian Sandoe, Esq.
Division of Investment Management
U.S. Securities and Exchange Commission                 VIA ELECTRONIC FILING
450 Fifth Street,
N.W., Fifth Floor
Washington, D.C. 20549


RE:      VANGUARD BALANCED INDEX FUND


Dear Mr. Sandoe:

     The  following  responds  to  your  comments  of  April  11,  2006  on  the
post-effective  amendment of the registration  statement of the above-referenced
registrant.  You commented on Post-Effective  Amendment No. 28 that was filed on
February 24, 2006.

COMMENT 1:        PROSPECTUS - PRIMARY INVESTMENT STRATEGIES
- ----------        ------------------------------------------


Comment:       Consider adding  information to this section regarding the credit
               quality   and   maturity   of   the   bond   portion,   and   the
               market-capitalization of the stock portion.

Response:      We have  considered  the  comment  and do not  plan  to make  the
               requested revision.  We include the more detailed  information in
               our Item 4  disclosure.  Since  Form N-1A  does not  specifically
               require  credit quality and market  capitalization  in the Item 2
               disclosure,  and  since  our  Item 2  disclosure  summarizes  the
               highlights  that  are  more  fully  fleshed  out  in  our  Item 4
               disclosure, we are comfortable with our existing disclosure.

COMMENT 2:        PROSPECTUS - FREQUENT TRADING OR MARKET TIMING
- ----------        ----------------------------------------------


Comment:       The Fund's broad  policies  with respect to frequent  trading and
               market-timing  are disclosed under the heading  "Frequent Trading
               or  Market-Timing."  However,  specific  policies  applicable  to
               discrete  types of  investors  are  disclosed  in various  places
               throughout the  "Investing  with  Vanguard"  section.  All of the
               Fund's policies  concerning  frequent  trading and  market-timing
               should be disclosed  together under the heading "Frequent Trading
               and Market-Timing."

Response:      We believe that the Fund's policies  against frequent trading and
               market-timing are properly  disclosed in the prospectus  pursuant


April 12, 2006
Page 2


               to Item 6(e)(4) of Form N-1A.  Item 6(e)(4) does not require that
               the specific  policies  applicable to each type of shareholder be
               disclosed together in the prospectus. As such, we believe that it
               is  appropriate  to have the  general  discussion  of the  Fund's
               policies  against frequent  trading and  market-timing  under the
               heading "Frequent  Trading or Market-Timing"  with a reference to
               the  "Investing  with Vanguard"  section where specific  policies
               applicable to different  types of shareholders  and  transactions
               are disclosed.

               We believe that removing the disclosure  from the "Investing with
               Vanguard"  section and  combining  the  disclosure  into a single
               "Frequent  Trading  and  Market-Timing"  section  would  make the
               discussion of transaction  policies  incomplete in the "Investing
               with Vanguard"  section.  Repeating the specific policies in both
               the  "Investing  with  Vanguard"  section and under the "Frequent
               Trading and Market-Timing"  heading would  unnecessarily  clutter
               the prospectus with duplicative disclosure.

COMMENT 3:        PROSPECTUS - INVESTMENT ADVISOR
- ----------        -------------------------------


Comment:       Please add  details  regarding  Mr.  Davis'  business  experience
               during the past 5 years.

Response:      We will add the requested clarification.


COMMENT 4:        SAI - INVESTMENT LIMITATIONS
- ----------        ----------------------------


Comment:       Although our SAI says that fundamental investment limitations are
               tested at the time securities are purchased,  there are borrowing
               requirements under the 1940 Act that require  adjustments to fund
               holdings within specific time periods if limits are exceeded. The
               SAI disclosure should be revised accordingly.

Response:      In  the  Investment   Policies  section  of  the  SAI  under  the
               "Borrowing" heading, we disclose the regulatory  requirement that
               a fund must have continuous  asset coverage of 300% of the amount
               borrowed.  We also disclose that if a fund's 300% asset  coverage
               declines  due to market  fluctuation,  a fund may be  required to
               sell some of its portfolio  holdings within three days to restore
               the 300% asset coverage.

               In the Investment Limitations section of the SAI, we disclose our
               fundamental  borrowing  limitation as follows,  "The Fund may not
               borrow in excess of 15% of its net assets,  and any borrowings by
               the   Fund   must   comply   with   all   applicable   regulatory
               requirements." (emphasis added)

     We think that these two sections,  when read together,  address the comment
sufficiently.

COMMENT 5:     SAI - DESCRIPTION OF COMPENSATION
- ----------     ---------------------------------


Comment:       Please  expand  on  the  discussion  of the  PM  compensation  by
               specifying  what  benchmark  index  each  PM  is  compared  to in
               determining his compensation.

Response:      We will make the requested revisions.


April 12, 2006
Page 3


COMMENT 6 - TANDY REQUIREMENTS
- ------------------------------


Comment:       The SEC is now requiring all registrants to provide at the end of
               response  letters  to  registration   statement   comments,   the
               following statements:


               o    The Fund is responsible for the adequacy and accuracy of the
                    disclosure in the filing.

               o    Staff  comments or changes in response to staff  comments in
                    the  filings  reviewed  by the  staff do not  foreclose  the
                    Commission  from  taking  any  action  with  respect  to the
                    filing.

               o    The Fund may not assert  staff  comments as a defense in any
                    proceeding  initiated by the  Commission or any person under
                    the federal securities laws of the United States.


Response:      As  required  by  the  SEC,   we  will   provide  the   foregoing
               acknowledgements.

                                    * * * * *

              As required by the SEC, the Fund acknowledges that:

               o    The Fund is responsible for the adequacy and accuracy of the
                    disclosure in the filing.

               o    Staff  comments or changes in response to staff  comments in
                    the  filings  reviewed  by the  staff do not  foreclose  the
                    Commission  from  taking  any  action  with  respect  to the
                    filing.

               o    The Fund may not assert  staff  comments as a defense in any
                    proceeding  initiated by the  Commission or any person under
                    the federal securities laws of the United States.

     Please  contact  me at  (610)  669-1538  with  any  questions  or  comments
regarding the above responses. Thank you.



Sincerely,



Judith L. Gaines
Associate Counsel
Securities Regulation, Legal Department