Report of Independent Registered Public Accounting
Firm

To the Board of Trustees of Vanguard Index Funds and
Shareholders of
Vanguard Total Stock Market Index Fund
Vanguard Extended Market Index Fund
Vanguard Mid-Cap Growth Index Fund
Vanguard Mid-Cap Value Index Fund
Vanguard Mid-Cap Index Fund
Vanguard Small-Cap Value Index Fund
Vanguard Small-Cap Growth Index Fund and
Vanguard Small-Cap Index Fund

In planning and performing our audits of the financial
statements of Vanguard Total Stock Market Index Fund,
Vanguard Extended Market Index Fund, Vanguard Mid-Cap
Growth Index Fund, Vanguard Mid-Cap Value Index Fund,
Vanguard Mid-Cap Index Fund, Vanguard Small-Cap Value
Index Fund, Vanguard Small-Cap Growth Index Fund and
Vanguard Small-Cap Index Fund (eight of the funds
constituting Vanguard Index Funds, hereafter collectively
referred to as the "Funds") as of and for the year ended
December 31, 2021, in accordance with the standards of
the Public Company Accounting Oversight Board (United
States) (PCAOB), we considered the Funds' internal control
over financial reporting, including controls over
safeguarding securities, as a basis for designing our
auditing procedures for the purpose of expressing our
opinion on the financial statements and to comply with the
requirements of Form N-CEN, but not for the purpose of
expressing an opinion on the effectiveness of the Funds'
internal control over financial reporting.  Accordingly, we do
not express an opinion on the effectiveness of the Funds'
internal control over financial reporting.

The management of the Funds is responsible for
establishing and maintaining effective internal control over
financial reporting.  In fulfilling this responsibility, estimates
and judgments by management are required to assess the
expected benefits and related costs of controls.  A
company's internal control over financial reporting is a
process designed to provide reasonable assurance
regarding the reliability of financial reporting and the
preparation of financial statements for external purposes in
accordance with generally accepted accounting principles.
A company's internal control over financial reporting
includes those policies and procedures that (1) pertain to
the maintenance of records that, in reasonable detail,
accurately and fairly reflect the transactions and
dispositions of the assets of the company; (2) provide
reasonable assurance that transactions are recorded as
necessary to permit preparation of financial statements in
accordance with generally accepted accounting principles,
and that receipts and expenditures of the company are
being made only in accordance with authorizations of
management and directors of the company; and (3) provide
reasonable assurance regarding prevention or timely
detection of unauthorized acquisition, use or disposition of a
company's assets that could have a material effect on the
financial statements.

Because of its inherent limitations, internal control over
financial reporting may not prevent or detect misstatements.
Also, projections of any evaluation of effectiveness to future
periods are subject to the risk that controls may become
inadequate because of changes in conditions, or that the
degree of compliance with the policies or procedures may
deteriorate.

A deficiency in internal control over financial reporting exists
when the design or operation of a control does not allow
management or employees, in the normal course of
performing their assigned functions, to prevent or detect
misstatements on a timely basis.  A material weakness is a
deficiency, or a combination of deficiencies, in internal
control over financial reporting, such that there is a
reasonable possibility that a material misstatement of the
company's annual or interim financial statements will not be
prevented or detected on a timely basis.

Our consideration of the Funds' internal control over
financial reporting was for the limited purpose described in
the first paragraph and would not necessarily disclose all
deficiencies in internal control over financial reporting that
might be material weaknesses under standards established
by the PCAOB.  However, we noted no deficiencies in the
Funds' internal control over financial reporting and its
operation, including controls over safeguarding securities,
that we consider to be a material weakness as defined
above as of December 31, 2021.

This report is intended solely for the information and use of
the Board of Trustees of Vanguard Index Funds and the
Securities and Exchange Commission and is not intended
to be and should not be used by anyone other than these
specified parties.


/s/ PricewaterhouseCoopers LLP
Philadelphia, Pennsylvania
February 17, 2022