Fidelity ZERO Large Cap Index Fund
Figures last verified October 31, 2026
Tracks Fidelity's proprietary US Large Cap Index — about 500 of the largest US stocks — at 0.00%.
FNILX is the S&P 500 with the serial numbers filed off. By building its own large-cap index instead of licensing Standard & Poor's, Fidelity avoids paying S&P's fees and passes the savings to exactly zero expense ratio. The holdings overlap the real S&P 500 almost completely; returns have tracked within a few hundredths of a percent since launch.
Versus FXAIX, the in-house S&P 500 fund at 0.015%, the calculus is the standard ZERO-fund trade: FNILX is free but Fidelity-captive; FXAIX costs almost nothing and travels. There's also a subtle difference — FNILX isn't bound to S&P's committee decisions, so the occasional index quirk (a Tesla inclusion saga, say) plays out slightly differently. None of it will decide your retirement. Pick by account type and move on.
S&P 500-style exposure with no fee, no index licensing, no minimum.
FNILX alternatives & comparable funds
If you’re weighing FNILX against the field, these are the funds most investors line it up against — same job, different provider, slightly different terms.
| Fund | Family | Expense Ratio | Minimum |
|---|---|---|---|
| FNILX — Fidelity ZERO Large Cap Index Fund | Fidelity | 0.00% | $0 |
| FXAIX — Fidelity 500 Index Fund | Fidelity | 0.015% | $0 |
| VFIAX — Vanguard 500 Index Fund Admiral Shares | Vanguard | 0.04% | $3,000 |
| FZROX — Fidelity ZERO Total Market Index Fund | Fidelity | 0.00% | $0 |
Frequently asked questions
What is the expense ratio of FNILX?
FNILX (Fidelity ZERO Large Cap Index Fund) has an expense ratio of 0.00%, which works out to roughly $0 per year for every $10,000 invested. That is a zero expense ratio — among the cheapest funds available anywhere.
What is the minimum investment for FNILX?
FNILX has no minimum initial investment — you can start with any amount.
What does FNILX invest in?
Tracks Fidelity's proprietary US Large Cap Index — about 500 of the largest US stocks — at 0.00%. It falls in the s&p 500 / large blend category and is an index fund.
What are good alternatives to FNILX?
The funds most often compared with FNILX are FXAIX, VFIAX, FZROX — broadly similar exposure from different providers, with small differences in fee, minimum, and portability that usually come down to which brokerage holds your account.
Expense ratio and minimum for FNILX drawn from Fidelity fund documentation; last verified October 31, 2026. Figures change — confirm against the official prospectus before investing. This review is editorial opinion, not investment advice.