Wealthy PotVTSAX vs VOO: Total Market Fund vs the S&P 500 ETF
VTSAX and VOO are two of the most popular ways to own U.S. stocks, but they differ on two axes at once: what they hold (the entire market vs the S&P 500) and how they trade (a mutual fund vs an ETF). Sorting those two questions out makes the choice easy. This guide uses figures pulled straight from Vanguard's fund documents.
The Short Answer
- Want the entire U.S. market (large, mid, and small caps) with classic mutual-fund mechanics? VTSAX. It holds ~3,531 stocks, charges 0.04%, and lets you invest exact dollar amounts, with a $3,000 minimum.
- Want the S&P 500 specifically, at the lowest fee, tradable intraday and portable to any broker? VOO. It holds ~506 large-cap stocks, charges 0.03%, and needs only one share (or a fractional share at Vanguard).
If you want a total-market ETF instead, that's VTI vs VOO; if you want the same total market as an ETF vs the mutual fund, see VTSAX vs VTI.
Two Differences, Not One
1. Coverage. VTSAX is a total-market fund, it owns essentially every investable U.S. stock, adding the mid caps and small caps that the S&P 500 leaves out. VOO owns only the S&P 500, the ~500 largest U.S. companies. Because large caps dominate by weight, the two move very closely, but VTSAX gives you the extra small/mid-cap slice.
2. Structure. VTSAX is a mutual fund, priced once a day at NAV, bought in exact dollar amounts, easy to automate, with a $3,000 minimum. VOO is an ETF, trading intraday on the exchange, with a one-share (or fractional) minimum and slightly better tax efficiency in a taxable account.
VTSAX vs VOO Side by Side
| Feature | VTSAX | VOO |
|---|---|---|
| Fund | Vanguard Total Stock Market (Admiral) | Vanguard S&P 500 ETF |
| Structure | Mutual fund | ETF |
| Index tracked | Morningstar US Total Market (formerly CRSP) | S&P 500 |
| What it covers | Entire U.S. market (large + mid + small) | Large-cap U.S. (S&P 500) |
| Expense ratio | 0.04% | 0.03% |
| Number of stocks | ~3,531 | ~506 |
| SEC 30-day yield | ~1.00% | ~0.98% |
| Minimum investment | $3,000 | 1 share (~$1 fractional at Vanguard) |
| 10-year return (avg annual, NAV) | 15.03% | 15.47% |
| Growth of $10,000 over those 10 years (hypothetical) | $40,550 | $42,140 |
VOO's slightly higher 10-year return reflects the recent dominance of mega-cap stocks; in periods when small and mid caps lead, VTSAX's broader reach can pull ahead. Over the long run the two are very close.
Which One Fits You
Choose VTSAX if: you want the whole U.S. market including small and mid caps, you like mutual-fund mechanics (exact-dollar automated investing, once-daily NAV), you're a Vanguard investor, and you can meet the $3,000 minimum. It's a complete one-fund U.S. equity core.
Choose VOO if: you specifically want the S&P 500, the lowest fee, intraday trading, no minimum, or the freedom to hold it at any broker. It's the more portable, marginally cheaper, slightly more tax-efficient option, just large-cap-only. Comparing S&P 500 wrappers? See SPY vs VOO and FXAIX vs VOO.
FAQ
Is VTSAX or VOO better?
They own different things: VTSAX is the total U.S. market (~3,531 stocks) as a mutual fund; VOO is the S&P 500 (~506 large caps) as an ETF. VTSAX adds small and mid caps and allows exact-dollar automated investing; VOO is a basis point cheaper, trades intraday, has no minimum, and is portable. Neither is universally better, pick by coverage and structure.
Do VTSAX and VOO hold the same stocks?
No. VOO holds the S&P 500's ~500 large caps; VTSAX holds those plus thousands of mid- and small-cap U.S. stocks (~3,531 total). They overlap heavily on the large caps that dominate both, which is why their returns are close.
Is VOO more tax-efficient than VTSAX?
In a taxable account the ETF structure (VOO) is generally slightly better at avoiding capital-gains distributions. In a tax-advantaged account (IRA/401k) the difference is irrelevant. Note VTSAX can be converted to its ETF share class (VTI) at Vanguard tax-free if you want the ETF structure with total-market coverage.
Should I hold both VTSAX and VOO?
Usually not, they overlap almost entirely on large caps, so holding both mostly duplicates exposure. Pick one U.S. core. If you want more than the S&P 500, VTSAX (or VTI) already includes the small and mid caps.
Related comparisons: VTSAX vs VTI · VTI vs VOO · FXAIX vs VOO · SPY vs VOO · All ETF comparisons
Primary sources: expense ratios, indexes, holdings, yields, and returns are from Vanguard's official fund fact sheets for VTSAX and VOO, both as of June 30, 2026 (SEC 30-day yields as of Aug 31, 2026). The CRSP-to-Morningstar index rename is per Morningstar's July 2026 announcement. For background, see the SEC's Investor.gov guide to mutual funds and ETFs.
This article is for educational purposes only and is not investment advice. Investing involves risk, including possible loss of principal, and past performance does not guarantee future results. Expense ratios and holdings change over time; confirm current figures on Vanguard's site before investing. Consult a qualified financial professional before making investment decisions.
