Total U.S. Market ETF Comparison: VTI vs SCHB vs ITOT
Direct answer: Total market ETFs hold every publicly traded U.S. company (approximately 3,500 to 4,000 stocks), not just the S&P 500's 500. The major options are VTI (Vanguard, 0.03%), SCHB (Schwab, 0.03%), and ITOT (iShares, 0.03%). They are functionally identical for most investors; differences in index methodology create minor tracking variation.
Total U.S. Market ETF Comparison
| Feature | VTI | SCHB | ITOT |
|---|---|---|---|
| Expense Ratio | 0.03% | 0.03% | 0.03% |
| AUM | ~$430B | ~$28B | ~$70B |
| Inception | May 2001 | Nov 2009 | Jan 2004 |
| Index | CRSP US Total Market | Dow Jones US Broad Market | S&P Total Market |
| Holdings Count (approx) | ~3,700 | ~2,500 | ~3,600 |
| Large Cap % (approx) | ~73% | ~72% | ~74% |
| Mid Cap % | ~18% | ~19% | ~17% |
| Small Cap % | ~9% | ~9% | ~9% |
Source: Vanguard: VTI ETF Details. Last verified: September 2026.
Frequently asked questions
What is the difference between VTI and VOO?
VTI tracks the entire U.S. stock market (approximately 3,700 stocks), while VOO tracks only the S&P 500 (500 stocks). VTI includes approximately 3,200 additional small and mid-cap stocks beyond what VOO holds. In practice, returns are very similar because large-cap stocks dominate both (approximately 70%+ weight). VTI provides broader diversification and slightly more exposure to small-cap stocks, which historically have offered a return premium over long periods. For most investors, either is a fine choice; VTI is marginally more diversified.
Does adding small caps to VTI help returns?
Historical evidence supports a small-cap premium (small stocks outperform large stocks over long periods), but it has been unreliable in recent decades. VTI's extra small-cap exposure (~9%) over VOO adds approximately 20-30 basis points of expected return advantage in theories based on Fama-French factors, but this can be negative in any given decade (small caps dramatically underperformed 2015-2024). For investors specifically targeting small-cap exposure, dedicated small-cap ETFs (IWM, VIOV) provide more concentrated exposure.
Why use a total market fund instead of S&P 500 only?
Total market funds provide broader diversification including small and mid-cap companies, which may grow faster than established large-caps and represent more of the U.S. economy. Historical CRSP data shows total market returns nearly identical to S&P 500 returns over long periods (within 0.1% annually), because large-cap dominance means the additional stocks have little impact. The main argument for total market is theoretical completeness: you own the whole market rather than an arbitrary 500-company selection. Neither approach is wrong; the difference is philosophically significant but financially minimal.