FZROX vs VTSAX: Which Should You Pick?
FZROX or VTSAX for the total U.S. market? A free Fidelity-only fund vs Vanguard's CRSP fund that converts to a portable ETF. When each one wins, and why.
FZROX and VTSAX are both total U.S. stock market mutual funds, so this is the closest apples-to-apples version of the Fidelity-vs-Vanguard question. FZROX is free and tracks Fidelity’s proprietary index; VTSAX charges 0.04% and tracks CRSP, the same index and portfolio as the VTI ETF. The difference that matters most is not the fee, it is that VTSAX can convert to an ETF and FZROX cannot leave Fidelity.
Quick answer
In a Fidelity tax-advantaged account, FZROX’s 0.00% fee is a fine reason to hold it and there is no tax cost. In a taxable account, VTSAX is usually the more flexible pick despite the 0.04% fee: it tracks the broader CRSP index, and at Vanguard it can convert tax-free (one way) to the VTI ETF, which is fully portable and tax-efficient. FZROX is Fidelity-only and cannot move in-kind, so leaving Fidelity later forces a taxable sale. The 0.04% gap is about $40 a year per $100k.
| FZROX | VTSAX | |
|---|---|---|
| Wrapper | Mutual fund | Mutual fund (Admiral shares) |
| Expense ratio | 0.00% | 0.04% |
| Index | Fidelity U.S. Total Investable Market (proprietary) | CRSP US Total Market |
| Holdings | ~2,688 | ~3,507 |
| Market coverage | Starts from top ~3,000 U.S. companies | Designed to cover ~100% of the investable market |
| Portability | Fidelity-only; not transferable | Vanguard-preferred; converts tax-free to VTI ETF at Vanguard (one way) |
| Minimum | $0 | $3,000 |
| Trading | End-of-day NAV, no spread | End-of-day NAV, no spread |
Fidelity and Vanguard fund documents. Expense ratios and holdings as of early 2026.
Because VTSAX and VTI are share classes of the same Vanguard fund, VTSAX holders at Vanguard can convert to the VTI ETF without triggering a taxable event, then move those shares to any brokerage. That escape hatch does not exist for FZROX. The holdings gap itself is modest in return terms: the names FZROX omits are mostly micro-caps with small aggregate weight.
Who should pick which
Pick FZROX if you
- Hold it in a Fidelity IRA or 401k.
- Want zero fees and no minimum to start.
- Plan to keep your accounts at Fidelity.
Pick VTSAX if you
- Want the broader CRSP index and a path to a portable ETF.
- Invest at Vanguard and like automatic dollar investing.
- Value the option to leave without a forced taxable sale.
The full reasoning
For the evidence behind why benchmark design and portability outweigh a near-zero fee, read Zero Fee, Non-Zero Benchmark Risk: Why Fidelity’s ZERO Funds Optimize the Wrong Variable. See also FZROX vs VTI and VTI vs VTSAX.
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