VINIX
VANGUARD INSTITUTIONAL INDEX FUND
VANGUARD INSTITUTIONAL INDEX FUNDS
Index fund
Expense ratio1
0.03%
Net assets2
$315.46B
Holdings2
505
Category
US Equity
2025 return3
17.84%

Investment objective & strategy

As of April 29, 2025 · prospectus

Objective. The Fund seeks to track the performance of a benchmark index that measures the investment return of large-capitalization stocks.

Strategy. The Fund employs an indexing investment approach designed to track the performance of the S&P 500 Index (the Index), a widely recognized benchmark of U.S. stock market performance that is dominated by the stocks of large U.S. companies. The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index. The Fund may become nondiversified, as defined under the investment Company Act of 1940, solely as a result of an index rebalance or market movement. The Fund employs an indexing investment approach designed to track the performance of the S&P 500 Index (the Index), a widely recognized benchmark of U.S. stock market performance that is dominated by the stocks of large U.S. companies. The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index. The Fund may become nondiversified, as defined under the investment Company Act of 1940, solely as a result of an index rebalance or market movement.

Top holdings

As of March 31, 2026 · N-PORT
SecurityTickerValue% of fund
NVIDIA CORP $23.89B 7.57%
APPLE INC $21.01B 6.66%
MICROSOFT CORP $15.50B 4.91%
AMAZON.COM INC $11.47B 3.64%
ALPHABET INC CL A $9.44B 2.99%
BROADCOM INC $8.27B 2.62%
ALPHABET INC CL C $7.56B 2.40%
META PLATFORMS INC CL A $7.06B 2.24%
TESLA INC $5.90B 1.87%
BERKSHIRE HATH-B $4.95B 1.57%
View all holdings →

Allocation by sector

As of March 31, 2026 · N-PORT
View portfolio breakdown →

Portfolio moves

Dec 31, 2025 → Mar 31, 2026
Opened
5
Exited
5
Increased
15
Decreased
485
Unchanged
0

How many positions this fund opened, exited, grew, trimmed, or left unchanged between its two most recent N-PORT snapshots — net changes between point-in-time reports, not a trade log.

View portfolio moves →

Similar funds

Funds whose portfolios most overlap this one, by weight

Advisers

As of December 31, 2025 · N-CEN
FirmRole
The Vanguard Group, Inc. Adviser

Footnotes

  1. Expense ratio as of April 29, 2025, from the fund's prospectus.
  2. Net assets and holdings count as of March 31, 2026, from the fund's N-PORT filing.
  3. Total return for calendar year 2025, before tax and after fund expenses. Computed by compounding the twelve monthly total returns the fund reported in its SEC N-PORT filings for 2025 (the latest prospectus does not yet chart this year).

Machine-readable: JSON · Markdown. Programmatic access via the agent surface.