TLT vs TSPI: 0% overlap
iShares 20+ Year Treasury Bond ETF and TSP I Fund — shown via international proxy share 0.0% 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
TLT and TSPI hold 1 of the same securities. The ten contributing most to the overlap figure:
| Holding | in TLT | in TSPI | Δ |
|---|---|---|---|
| CASH | 0.0% | 2.4% | 2.4% |
Where TLT 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 | TLT | TSPI | Δ |
|---|---|---|---|
| Treasuries | 100.0% | 0.0% | +100.0pp |
| Information Technology | 0.0% | 20.9% | −20.9pp |
| Financials | 0.0% | 19.7% | −19.7pp |
| Industrials | 0.0% | 13.8% | −13.8pp |
| Unclassified | 0.0% | 9.1% | −9.1pp |
| Consumer Discretionary | 0.0% | 7.5% | −7.5pp |
| Health Care | 0.0% | 5.3% | −5.3pp |
| Materials | 0.0% | 5.2% | −5.2pp |
Δ is TLT 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
100.0% of TLT by weight, held in no part of TSPI.
97.6% of TSPI by weight, held in no part of TLT.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| TLT | TSPI | |
|---|---|---|
| Top 10 holdings | 100.0% | 16.3% |
| Positions held | 3 | 8,453 |
| Cost per $10,000 held, per year | $15 | $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 TLT and TSPI overlap?
TLT and TSPI overlap 0.0% by portfolio weight — largely distinct portfolios. They share 1 holdings. The figure comes from current issuer holdings files (TLT as of 2026-07-23, TSPI as of 2026-06-30).
How is the overlap between TLT and TSPI calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If TLT 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 TLT and TSPI?
That depends on your goals — we state facts, not advice. At 0.0% overlap, each fund still contributes meaningfully distinct exposure.
What does TLT own that TSPI doesn't?
TLT holds 3 positions and TSPI holds 8,453; 1 of TLT's positions don't appear in TSPI at all, and they are 100.0% of TLT by weight.
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Related comparisons
Sources: issuer holdings files, TLT as of 2026-07-23, TSPI as of 2026-06-30. Weights are fractions of each fund. Diagnostics, not advice.