VBTLX vs VTHRX: 29% overlap
Vanguard Total Bond Market Index Admiral and Vanguard Target Retirement 2030 share 29.3% 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 3 months apart — VTHRX as of 2026-03-31, 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 1.7. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
VBTLX and VTHRX hold 2,047 of the same securities. The ten contributing most to the overlap figure:
| Holding | in VBTLX | in VTHRX | Δ |
|---|---|---|---|
| UST-3-10Y | 21.3% | 6.0% | 15.3% |
| AGENCY-MBS | 20.3% | 5.7% | 14.6% |
| UST-0-3Y | 16.7% | 4.7% | 12.0% |
| UST-10Y+ | 10.2% | 2.9% | 7.3% |
| CASH | 1.1% | 1.9% | 0.8% |
| 46647P | 0.6% | 0.2% | 0.4% |
| 06051G | 0.5% | 0.1% | 0.4% |
| 459058 | 0.4% | 0.1% | 0.3% |
| 68389X | 0.3% | 0.1% | 0.2% |
| 023135 | 0.3% | 0.1% | 0.2% |
Where VBTLX and VTHRX 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 | VBTLX | VTHRX | Δ |
|---|---|---|---|
| Treasuries | 48.2% | 13.6% | +34.6pp |
| Information Technology | 0.0% | 17.3% | −17.3pp |
| MBS Pass-Through | 20.3% | 5.7% | +14.6pp |
| Unclassified | 0.7% | 13.3% | −12.7pp |
| Corporate — industrial & other | 14.6% | 4.4% | +10.3pp |
| Industrials | 0.0% | 6.9% | −6.9pp |
| Consumer Discretionary | 0.0% | 5.0% | −5.0pp |
| Health Care | 0.0% | 4.6% | −4.6pp |
Δ is VBTLX minus VTHRX, 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 VBTLX by weight, held in no part of VTHRX.
69.5% of VTHRX by weight, held in no part of VBTLX.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| VBTLX | VTHRX | |
|---|---|---|
| Top 10 holdings | 71.7% | 28.9% |
| Positions held | 2,047 | 7 |
| Cost per $10,000 held, per year | $4 | $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 VBTLX and VTHRX overlap?
VBTLX and VTHRX overlap 29.3% by portfolio weight — moderate overlap. They share 2,047 holdings. The figure comes from current issuer holdings files (VBTLX as of 2026-06-30, VTHRX as of 2026-03-31).
How is the overlap between VBTLX and VTHRX calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If VBTLX holds a stock at 6% and VTHRX 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 VBTLX and VTHRX?
That depends on your goals — we state facts, not advice. At 29.3% overlap, each fund still contributes meaningfully distinct exposure.
What does VBTLX own that VTHRX doesn't?
VBTLX holds 2,047 positions and VTHRX holds 7; 0 of VBTLX's positions don't appear in VTHRX at all, and they are 0.0% of VBTLX by weight.
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Related comparisons
Sources: issuer holdings files, VBTLX as of 2026-06-30, VTHRX as of 2026-03-31. Weights are fractions of each fund. Diagnostics, not advice.