SMXAX
SIIT EXTENDED MARKET INDEX FUND
SEI INSTITUTIONAL INVESTMENTS TRUST
Index fund
Expense ratio1
0.20%
Net assets2
$1.24B
Holdings2
2293
Category
US Equity
2025 return3
12.88%

Investment objective & strategy

As of Nov. 18, 2025 · prospectus

Strategy. In the Fund Summary of the Large Cap Index Fund, S & P 500 Index Fund and Extended Market Index Fund, under the sub-heading "Principal Investment Strategies," the following text is hereby added at the end of the first paragraph: The Fund may become "non-diversified," as defined in the Investment Company Act of 1940 Act, as amended (the "1940 Act"), as a result of a change in relative market capitalization or index weighting of one or more constituents of the Index. In the Fund Summary of the Large Cap Index Fund, S & P 500 Index Fund and Extended Market Index Fund, under the sub-heading "Principal Investment Strategies," the following text is hereby added at the end of the first paragraph: The Fund may become "non-diversified," as defined in the Investment Company Act of 1940 Act, as amended (the "1940 Act"), as a result of a change in relative market capitalization or index weighting of one or more constituents of the Index.

Top holdings

As of Feb. 28, 2026 · N-PORT
SecurityTickerValue% of fund
SEI DAILY INCOME TRUST GOVERNMENT FUND (#36) $15.72M 1.26%
VERTIV HOLDINGS CO $14.99M 1.20%
Spotify Technology SA $12.24M 0.98%
MARVELL TECHNOLOGY INC $10.91M 0.88%
Anglogold Ashanti Plc $9.93M 0.80%
SNOWFLAKE INC CL A $8.54M 0.69%
CLOUDFLARE INC-A $8.33M 0.67%
US ULTRA BOND CBT Sep25 $8.17M 0.66%
CHENIERE ENERGY INC $7.77M 0.62%
NU Holdings Ltd/Cayman Islands $7.73M 0.62%
View all holdings →

Allocation by sector

As of February 28, 2026 · N-PORT
View portfolio breakdown →

Portfolio moves

Nov 30, 2025 → Feb 28, 2026
Opened
60
Exited
57
Increased
591
Decreased
51
Unchanged
1591

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.

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Similar funds

Funds whose portfolios most overlap this one, by weight
FundOverlapNet exp.
VANGUARD EXTENDED MARKET INDEX FUND · VEXMX, VEXAX, VIEIX, VXF, VEMPX, VSEMX 80% 0.02%
Fidelity Extended Market Index Fund · FSMAX 79% 0.03%
STATE STREET SMALL/MID CAP EQUITY INDEX PORTFOLIO · SSMHX 75% 0.02%
View all similar funds →

Advisers

As of May 31, 2025 · N-CEN
FirmRole
SEI INVESTMENTS MANAGEMENT Corporation Adviser
SSGA Funds Management, Inc. Sub-adviser

Footnotes

  1. Expense ratio as of September 26, 2025, from the fund's prospectus.
  2. Net assets and holdings count as of February 28, 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).

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