FXNAX vs TSPI: 1% overlap
Fidelity U.S. Bond Index and TSP I Fund — shown via international proxy share 1.3% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
Different holding dates. These holdings were published about 4 months apart — FXNAX as of 2026-02-28, the rest through 2026-06-30. Each fund is compared using its most recent file, so any trading in between shows up as a difference.
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
FXNAX and TSPI hold 1 of the same securities. The ten contributing most to the overlap figure:
| Holding | in FXNAX | in TSPI | Δ |
|---|---|---|---|
| CASH | 1.3% | 2.4% | 1.1% |
Where FXNAX and TSPI 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 | FXNAX | TSPI | Δ |
|---|---|---|---|
| Treasuries | 45.4% | 0.0% | +45.4pp |
| Information Technology | 0.0% | 20.9% | −20.9pp |
| MBS Pass-Through | 16.5% | 0.0% | +16.5pp |
| Corporate — industrial & other | 14.1% | 0.0% | +14.1pp |
| Industrials | 0.0% | 13.8% | −13.8pp |
| Financials | 8.6% | 19.7% | −11.1pp |
| Consumer Discretionary | 0.0% | 7.5% | −7.5pp |
| Health Care | 0.0% | 5.3% | −5.3pp |
Δ is FXNAX minus TSPI, 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
99.9% of FXNAX by weight, held in no part of TSPI.
97.6% of TSPI by weight, held in no part of FXNAX.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| FXNAX | TSPI | |
|---|---|---|
| Top 10 holdings | 69.4% | 16.3% |
| Positions held | 1,266 | 8,453 |
| Cost per $10,000 held, per year | $3 | $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 FXNAX and TSPI overlap?
FXNAX and TSPI overlap 1.3% by portfolio weight — largely distinct portfolios. They share 1 holdings. The figure comes from current issuer holdings files (FXNAX as of 2026-02-28, TSPI as of 2026-06-30).
How is the overlap between FXNAX and TSPI calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If FXNAX holds a stock at 6% and TSPI 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 FXNAX and TSPI?
That depends on your goals — we state facts, not advice. At 1.3% overlap, each fund still contributes meaningfully distinct exposure.
What does FXNAX own that TSPI doesn't?
FXNAX holds 1,266 positions and TSPI holds 8,453; 1,265 of FXNAX's positions don't appear in TSPI at all, and they are 99.9% of FXNAX by weight.
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Related comparisons
Sources: issuer holdings files, FXNAX as of 2026-02-28, TSPI as of 2026-06-30. Weights are fractions of each fund. Diagnostics, not advice.