REPORT OF INDEPENDENT REGISTERED PUBLIC
ACCOUNTING FIRM

To the Shareholders of iShares MSCI EAFE International
Index Fund and iShares Russell 2000 Small-Cap Index
Fund and the Board of Directors of BlackRock Index
Funds, Inc.:

In planning and performing our audits of the financial
statements of iShares MSCI EAFE International Index Fund
and iShares Russell 2000 Small-Cap Index Fund of
BlackRock Index Funds, Inc. (the "Funds"), as of and for the
year ended December 31, 2019, 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 express no such opinion.

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 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 for safeguarding
securities, that we consider to be a material weakness, as
defined above, as of December 31, 2019.

This report is intended solely for the information and use of
management and the Board of Directors of the 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.

Deloitte & Touche LLP
Boston, Massachusetts
February 24, 2020