TSPI vs TSPS: 4% overlap
TSP I Fund — shown via international proxy and TSP S Fund — shown via extended-market proxy share 4.5% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
You would hold two tickers and get the diversification of 2.0. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
TSPI and TSPS hold 164 of the same securities. The ten contributing most to the overlap figure:
| Holding | in TSPI | in TSPS | Δ |
|---|---|---|---|
| CASH | 2.4% | 3.8% | 1.3% |
| AAL | 0.1% | 0.1% | 0.0% |
| CFR | 0.3% | 0.1% | 0.2% |
| RKT | 0.1% | 0.2% | 0.1% |
| ALV | 0.4% | 0.1% | 0.3% |
| CSL | 0.1% | 0.2% | 0.1% |
| ORA | 0.1% | 0.1% | 0.0% |
| NXT | 0.1% | 0.2% | 0.1% |
| SUNB | 0.1% | 0.3% | 0.3% |
| AIR | 0.3% | 0.1% | 0.2% |
Where TSPI and TSPS differ
Sector weights as a share of each fund, ordered by the size of the gap rather than the size of the sector — two funds that overlap heavily still usually diverge somewhere.
| Sector | TSPI | TSPS | Δ |
|---|---|---|---|
| Unclassified | 9.1% | 1.0% | +8.1pp |
| Health Care | 5.3% | 13.2% | −7.9pp |
| Industrials | 13.8% | 19.8% | −6.0pp |
| Financials | 19.7% | 13.9% | +5.8pp |
| Information Technology | 20.9% | 17.6% | +3.3pp |
| Real Estate | 1.9% | 4.8% | −2.9pp |
| Consumer Staples | 4.9% | 2.7% | +2.1pp |
| Cash and/or Derivatives | 2.5% | 3.8% | −1.3pp |
Δ is TSPI minus TSPS, in percentage points. Sector data is not published by every issuer, so “Unclassified” is a real category rather than a gap in the table.
What each fund holds alone
93.1% of TSPI by weight, held in no part of TSPS.
89.1% of TSPS by weight, held in no part of TSPI.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| TSPI | TSPS | |
|---|---|---|
| Top 10 holdings | 16.3% | 10.6% |
| Positions held | 8,453 | 3,327 |
| Cost per $10,000 held, per year | $5 | $5 |
Cost is the expense ratio applied to $10,000; it excludes any brokerage commission, bid-ask spread or tax consequence. Figures are facts about the funds, not a suggestion about which to hold.
Frequently asked
How much do TSPI and TSPS overlap?
TSPI and TSPS overlap 4.5% by portfolio weight — largely distinct portfolios. They share 164 holdings. The figure comes from current issuer holdings files (TSPI as of 2026-06-30, TSPS as of 2026-06-30).
How is the overlap between TSPI and TSPS calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If TSPI holds a stock at 6% and TSPS holds the same stock at 4%, 4% counts as shared. The result is bounded between 0% and 100%, and it is computed after looking through any fund-of-funds to the underlying holdings.
Is it redundant to hold both TSPI and TSPS?
That depends on your goals — we state facts, not advice. At 4.5% overlap, each fund still contributes meaningfully distinct exposure.
What does TSPI own that TSPS doesn't?
TSPI holds 8,453 positions and TSPS holds 3,327; 8,289 of TSPI's positions don't appear in TSPS at all, and they are 93.1% of TSPI by weight.
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Related comparisons
Sources: issuer holdings files, TSPI as of 2026-06-30, TSPS as of 2026-06-30. Weights are fractions of each fund. Diagnostics, not advice.