FZROX vs. FSKAX: Fidelity ZERO Total Market I or Fidelity Total Market Index Fund?
Figures last verified October 31, 2026
Fidelity's own total-market civil war: the free proprietary-index fund against the 0.015% Dow-Jones-tracking one. The entire decision hinges on one feature most people never use — portability.
| FZROX | FSKAX | |
|---|---|---|
| Fund | Fidelity ZERO Total Market Index Fund | Fidelity Total Market Index Fund |
| Family | Fidelity | Fidelity |
| Category | Total US Market | Total US Market |
| Type | Index | Index |
| Expense ratio | 0.00% | 0.015% |
| Cost per $10k/yr | $0 | $1.50 |
| Minimum | $0 | $0 |
| Strategy | Tracks Fidelity's proprietary US Total Investable Market Index — about 2,700 stocks — at a 0.00% expense ratio. | Tracks the Dow Jones US Total Stock Market Index — about 3,800 stocks across the full US market. |
IRA money: FZROX, because free beats 0.015% and you'd sell to move anyway. Taxable money: FSKAX, because it can transfer in kind to another broker without triggering a tax bill. The performance difference is statistical noise.
About FZROX
The expense ratio is zero. Not low — zero. When Fidelity launched the ZERO funds in 2018 it was a marketing shot at Vanguard, and nearly eight years on, the funds have done what they promised: tracked the broad US market at no cost, with performance right on top of VTSAX and FSKAX. The free lunch, in this narrow case, is real.
About FSKAX
FSKAX is Fidelity's answer to VTSAX, and the answer undercuts the question: the entire US stock market at 0.015% instead of 0.04%, with no minimum instead of $3,000. The index differs by name — Dow Jones US Total Market versus CRSP — but the portfolios overlap so completely that performance differences are statistical noise.
Whichever you pick, the principle is the same one that runs through this whole site: minimize cost, hold for decades, ignore the noise. See how both stack up against the field in our best index funds by category, or run the numbers yourself with the expense ratio calculator.
Expense ratios and minimums drawn from fund provider documentation; last verified October 31, 2026. Editorial opinion, not investment advice. Confirm figures against the official prospectus before investing.