Vanguard Mid-Cap Index Fund Admiral Shares
Figures last verified October 31, 2026
Tracks the CRSP US Mid Cap Index — about 300 middle-sized US companies.
Mid caps are the market's quiet overachievers: big enough to have survived the startup gauntlet, small enough to still double. Over long stretches, the segment has matched or beaten both its larger and smaller siblings with less drama than small caps. VIMAX captures it with characteristic Vanguard plainness — a few hundred companies, 0.05%, nothing to monitor.
Most investors get their mid-cap exposure invisibly through a total-market fund and never need a dedicated slice. VIMAX earns a spot when your 401(k) pairs an S&P 500 fund with nothing else, leaving a mid/small hole — or when you want to deliberately overweight the middle. It does its one job at a price that makes active mid-cap funds, which routinely charge 15x more, hard to justify.
Filling the mid-cap slot in a sliced portfolio.
VIMAX alternatives & comparable funds
If you’re weighing VIMAX 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 |
|---|---|---|---|
| VIMAX — Vanguard Mid-Cap Index Fun… | Vanguard | 0.05% | $3,000 |
| FSMDX — Fidelity Mid Cap Index Fund | Fidelity | 0.025% | $0 |
| VEXAX — Vanguard Extended Market I… | Vanguard | 0.06% | $3,000 |
| VTSAX — Vanguard Total Stock Marke… | Vanguard | 0.04% | $3,000 |
Head-to-head comparisons
Frequently asked questions
What is the expense ratio of VIMAX?
VIMAX (Vanguard Mid-Cap Index Fund Admiral Shares) has an expense ratio of 0.05%, which works out to roughly $5 per year for every $10,000 invested. That is very low by industry standards, where the average fund still charges well over 0.40%.
What is the minimum investment for VIMAX?
VIMAX requires a minimum initial investment of $3,000.
What does VIMAX invest in?
Tracks the CRSP US Mid Cap Index — about 300 middle-sized US companies. It falls in the mid cap category and is an index fund.
What are good alternatives to VIMAX?
The funds most often compared with VIMAX are FSMDX, VEXAX, VTSAX — 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 VIMAX drawn from Vanguard fund documentation; last verified October 31, 2026. Figures change — confirm against the official prospectus before investing. This review is editorial opinion, not investment advice.