VBIAX vs VFFVX: 9% overlap

Vanguard Balanced Index Admiral and Vanguard Target Retirement 2055 share 9.5% 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 — VBIAX, VFFVX 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.

Hold both, 50/50
1.9Effective Funds

You would hold two tickers and get the diversification of 1.9. Two funds that shared nothing would score 2.0; two identical funds score 1.0.

Overlap
9.5%
VBIAX expense ratio
0.07%
VFFVX expense ratio
0.08%

Top shared holdings

VBIAX and VFFVX hold 2,221 of the same securities. The ten contributing most to the overlap figure:

Holdingin VBIAXin VFFVXΔ
CASH1.8%1.9%0.1%
AGENCY-MBS8.1%1.4%6.7%
LLY0.7%0.7%0.0%
IBM0.2%0.2%0.0%
APH0.1%0.2%0.0%
MCD0.2%0.1%0.1%
TMO0.2%0.1%0.0%
QCOM0.1%0.1%0.0%
DIS0.2%0.1%0.0%
ETN0.1%0.1%0.0%

Where VBIAX and VFFVX 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.

SectorVBIAXVFFVXΔ
Unclassified55.1%6.1%+49.0pp
Information Technology1.0%26.3%25.3pp
Treasuries19.1%3.3%+15.9pp
Financials3.6%14.1%10.5pp
Industrials0.7%10.6%9.9pp
Consumer Discretionary0.5%7.6%7.1pp
MBS Pass-Through8.1%1.4%+6.7pp
Health Care1.2%7.0%5.8pp

Δ is VBIAX minus VFFVX, 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

Only in VBIAX
2,897 positions

74.0% of VBIAX by weight, held in no part of VFFVX.

Only in VFFVX
14,461 positions

89.9% of VFFVX by weight, held in no part of VBIAX.

A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.

Concentration and cost

VBIAXVFFVX
Top 10 holdings45.2%19.2%
Positions held5,1196
Cost per $10,000 held, per year$7$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 VBIAX and VFFVX overlap?

VBIAX and VFFVX overlap 9.5% by portfolio weight — largely distinct portfolios. They share 2,221 holdings. The figure comes from current issuer holdings files (VBIAX as of 2026-03-31, VFFVX as of 2026-03-31).

How is the overlap between VBIAX and VFFVX calculated?

As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If VBIAX holds a stock at 6% and VFFVX 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 VBIAX and VFFVX?

That depends on your goals — we state facts, not advice. At 9.5% overlap, each fund still contributes meaningfully distinct exposure.

What does VBIAX own that VFFVX doesn't?

VBIAX holds 5,119 positions and VFFVX holds 6; 2,897 of VBIAX's positions don't appear in VFFVX at all, and they are 74.0% of VBIAX by weight.

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Related comparisons

Sources: issuer holdings files, VBIAX as of 2026-03-31, VFFVX as of 2026-03-31. Weights are fractions of each fund. Diagnostics, not advice.