TLT vs VTWNX: 4% overlap
iShares 20+ Year Treasury Bond ETF and Vanguard Target Retirement 2020 share 3.6% 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 — VTWNX as of 2026-03-31, the rest through 2026-07-23. 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
TLT and VTWNX hold 2 of the same securities. The ten contributing most to the overlap figure:
| Holding | in TLT | in VTWNX | Δ |
|---|---|---|---|
| UST-10Y+ | 100.0% | 3.6% | 96.4% |
| CASH | 0.0% | 1.7% | 1.7% |
Where TLT and VTWNX 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 | VTWNX | Δ |
|---|---|---|---|
| Treasuries | 100.0% | 17.1% | +82.9pp |
| Unclassified | 0.0% | 29.8% | −29.8pp |
| Information Technology | 0.0% | 10.0% | −10.0pp |
| Financials | 0.0% | 8.2% | −8.2pp |
| MBS Pass-Through | 0.0% | 7.2% | −7.2pp |
| Corporate — industrial & other | 0.0% | 5.5% | −5.5pp |
| Industrials | 0.0% | 4.0% | −4.0pp |
| Consumer Discretionary | 0.0% | 2.9% | −2.9pp |
Δ is TLT minus VTWNX, 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
0.0% of TLT by weight, held in no part of VTWNX.
94.6% of VTWNX 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 | VTWNX | |
|---|---|---|
| Top 10 holdings | 100.0% | 44.9% |
| Positions held | 3 | 7 |
| Cost per $10,000 held, per year | $15 | $8 |
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 VTWNX overlap?
TLT and VTWNX overlap 3.6% by portfolio weight — largely distinct portfolios. They share 2 holdings. The figure comes from current issuer holdings files (TLT as of 2026-07-23, VTWNX as of 2026-03-31).
How is the overlap between TLT and VTWNX 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 VTWNX 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 VTWNX?
That depends on your goals — we state facts, not advice. At 3.6% overlap, each fund still contributes meaningfully distinct exposure.
What does TLT own that VTWNX doesn't?
TLT holds 3 positions and VTWNX holds 7; 0 of TLT's positions don't appear in VTWNX at all, and they are 0.0% of TLT by weight.
You probably hold more than two funds
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Related comparisons
Sources: issuer holdings files, TLT as of 2026-07-23, VTWNX as of 2026-03-31. Weights are fractions of each fund. Diagnostics, not advice.