TSP I Fund: what's actually inside it
Officially the International Stock Index Investment Fund. International company stocks, developed and emerging markets. Tracks a broad index of non-US developed and emerging markets.
8,589 holdings · expense ratio 0.054% · top 10 = 15.2% · concentration score 2.9/100 · holdings as of 2026-09-30
Top 25 holdings
| # | Holding | Weight | |
|---|---|---|---|
| 1 | 2330 | 4.28% | |
| 2 | CASH | 2.25% | |
| 3 | 005930 | 2.04% | |
| 4 | 000660 | 1.67% | |
| 5 | ASML | 1.55% | |
| 6 | 700 | 0.77% | |
| 7 | HSBA | 0.76% | |
| 8 | ROP | 0.66% | |
| 9 | SAN | 0.65% | |
| 10 | SHEL | 0.62% | |
| 11 | RY | 0.62% | |
| 12 | NOVN | 0.60% | |
| 13 | SU | 0.58% | |
| 14 | 9988 | 0.57% | |
| 15 | 8306 | 0.57% | |
| 16 | AZN | 0.54% | |
| 17 | NESN | 0.52% | |
| 18 | 2454 | 0.51% | |
| 19 | SIE | 0.51% | |
| 20 | BHP | 0.48% | |
| 21 | SAP | 0.48% | |
| 22 | 7203 | 0.44% | |
| 23 | TD | 0.43% | |
| 24 | SHOP | 0.41% | |
| 25 | ALV | 0.40% |
Sector split
Overlap with the other TSP funds
The question a federal employee can actually act on: holding two of these, how much is the same underlying company?
| Paired with | Overlap | Effective Funds (50/50) |
|---|---|---|
| TSP S Fund | 4.2% | 2.0 |
| TSP F Fund | 2.2% | 2.0 |
| TSP C Fund | 0.8% | 2.0 |
What has changed
Between July 2026 and September 2026, from 3 months on record:
| July 2026 | September 2026 | Change | |
|---|---|---|---|
| Largest holding | 23304.0% | 23304.3% | +0.2pp |
| Top 10 holdings | 14.8% | 15.2% | +0.4pp |
| Positions published | 8,468 | 8,589 | +121 |
One point per month, taken from the issuer's published holdings file. Tracking began July 2026 — figures from before then were not retained.
Frequently asked
What does the TSP I Fund actually hold?
The I Fund — officially the International Stock Index Investment Fund — tracks a broad index of non-US developed and emerging markets. The Thrift Savings Plan does not publish a holdings list and does not file SEC form N-PORT, so this page shows the 8,589 positions of VXUS, which tracks the same index, as of 2026-09-30. The largest position is 2330 at 4.3%, and the top ten are 15.2% of the fund.
Is this the TSP's real holdings data?
No, and that distinction matters. It is a labelled proxy: a different fund tracking the same index, not the I Fund itself. VXUS holds a broad ex-US basket and is the closest covered equivalent to the I Fund's mandate. Index funds tracking the same benchmark hold nearly identical portfolios, so the picture is close — but the weights are VXUS's, not the TSP's, and the TSP has never published its own.
How much do the TSP funds overlap each other?
The I Fund overlaps the S Fund 4.2% by weight — S Fund 4.2%, F Fund 2.2%, C Fund 0.8%. Overlap is the sum of the smaller weight in each fund over every holding both own, computed from the proxy holdings described above.
Why isn't the G Fund shown?
The G Fund — officially the Government Securities Investment Fund — is deliberately absent. It holds non-marketable US Treasury securities issued only to the TSP, which are not traded anywhere and have no market equivalent. Showing it through a bond fund would misrepresent an instrument whose defining feature is that its principal cannot fall.
Most federal employees hold more than the TSP
A TSP account is rarely the whole picture — there is often an IRA, a spouse's 401(k), or a brokerage account alongside it. Paste them all together to see the real overlap between your I Fund and everything else you own, and your own Effective Funds number. Free, no account, nothing stored.
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How it overlaps the other TSP funds
TSP I Fund shown via VXUS, holdings as of 2026-09-30. The TSP publishes no holdings of its own. Weights are fractions of the fund. Diagnostics, not advice.