FXAIX vs VTSAX: 80% overlap

Fidelity 500 Index and Vanguard Total Stock Market Index Admiral share 80.2% 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 — FXAIX 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.

Hold both, 50/50
1.2Effective Funds

You would hold two tickers and get the diversification of 1.2. Two funds that shared nothing would score 2.0; two identical funds score 1.0.

Overlap
80.2%
FXAIX expense ratio
0.01%
VTSAX expense ratio
0.04%

Top shared holdings

FXAIX and VTSAX hold 470 of the same securities. The ten contributing most to the overlap figure:

Holdingin FXAIXin VTSAXΔ
NVDA7.3%6.3%1.0%
AAPL6.6%5.8%0.8%
MSFT5.0%3.8%1.1%
AMZN3.5%3.2%0.3%
GOOGL3.1%2.9%0.2%
AVGO2.6%2.5%0.1%
GOOG2.5%2.3%0.2%
META2.4%1.7%0.7%
TSLA1.9%1.6%0.3%
LLY1.4%1.4%0.0%

Where FXAIX and VTSAX 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.

SectorFXAIXVTSAXΔ
Information Technology31.8%35.2%3.4pp
Unclassified3.3%0.2%+3.1pp
Industrials8.3%10.4%2.1pp
Communication Services10.5%9.1%+1.5pp
Consumer Staples5.4%4.3%+1.0pp
Materials1.5%2.0%0.6pp
Consumer Discretionary9.7%9.2%+0.5pp
Cash and/or Derivatives0.3%0.6%0.3pp

Δ is FXAIX minus VTSAX, 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 FXAIX
35 positions

3.4% of FXAIX by weight, held in no part of VTSAX.

Only in VTSAX
3,025 positions

15.1% of VTSAX by weight, held in no part of FXAIX.

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

Concentration and cost

FXAIXVTSAX
Top 10 holdings36.4%31.9%
Positions held5063,495
Cost per $10,000 held, per year$1$4

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 FXAIX and VTSAX overlap?

FXAIX and VTSAX overlap 80.2% by portfolio weight — substantial duplication if you hold both. They share 470 holdings. The figure comes from current issuer holdings files (FXAIX as of 2026-02-28, VTSAX as of 2026-06-30).

How is the overlap between FXAIX and VTSAX calculated?

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

That depends on your goals — we state facts, not advice. At 80.2% overlap, most of what one fund holds, the other holds too. Expense ratios: FXAIX 0.01% versus VTSAX 0.04%.

What does FXAIX own that VTSAX doesn't?

FXAIX holds 506 positions and VTSAX holds 3,495; 35 of FXAIX's positions don't appear in VTSAX at all, and they are 3.4% of FXAIX by weight.

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Related comparisons

Sources: issuer holdings files, FXAIX as of 2026-02-28, VTSAX as of 2026-06-30. Weights are fractions of each fund. Diagnostics, not advice.