Index Fund Comparison
Compare S&P 500, total market, and international index funds across Fidelity, Vanguard, Schwab, and iShares
Key Numbers
FZROX/FNILX
0.00% ER
VOO/VTI
0.03% ER
FXAIX
0.015% ER
Performance
Nearly Identical
Index funds offer low-cost, diversified exposure to the stock market. At today’s expense ratios (0.00%–0.04%), the performance difference between major providers is negligible — pick the fund that’s most convenient at your brokerage.
Quick pick by brokerage
Fidelity: FZROX (0.00%) or FSKAX (0.015%) for total market — or FNILX / FXAIX for S&P 500.
Vanguard: VTI (0.03%) for total market — or VOO (0.03%) for S&P 500.
Schwab: SWTSX (0.03%) for total market — or SWPPX (0.02%) for S&P 500.
Any brokerage: IVV (0.03%) and ITOT (0.03%) from iShares trade commission-free nearly everywhere.
Core Funds at a Glance
| Category | Fidelity | Vanguard | Schwab | iShares |
|---|---|---|---|---|
| S&P 500 | FXAIX 0.015% | VOO / VFIAX 0.03% / 0.04% | SWPPX 0.02% | IVV 0.03% |
| Total US Market | FSKAX 0.015% | VTI / VTSAX 0.03% / 0.04% | SWTSX 0.03% | ITOT 0.03% |
| International | FTIHX 0.06% | VXUS / VTIAX 0.08% / 0.12% | SWISX* 0.06% | IXUS 0.07% |
| Total Bond | FXNAX 0.025% | BND / VBTLX 0.03% / 0.05% | SWAGX 0.04% | AGG 0.03% |
Expense ratios as of early 2026. ETFs shown first (e.g., VOO), mutual funds second (e.g., VFIAX). *SWISX covers developed markets only (MSCI EAFE); it excludes emerging markets.
Fidelity ZERO funds (FZROX, FNILX, FZILX, FZIPX) carry a 0.00% expense ratio but track proprietary Fidelity indexes rather than the S&P 500 or CRSP. Performance is nearly identical to their standard counterparts. Available only at Fidelity.
S&P 500 Index Funds
S&P 500 funds track the 500 largest US companies, representing about 80% of total US market capitalization. These are the most widely held index funds.
| Fund | Provider | Type | Expense Ratio | Minimum | AUM |
|---|---|---|---|---|---|
| FNILX | Fidelity | Mutual Fund | 0.00% | $0 | $8B+ |
| FXAIX | Fidelity | Mutual Fund | 0.015% | $0 | $700B+ |
| SWPPX | Schwab | Mutual Fund | 0.02% | $0 | $90B+ |
| VOO | Vanguard | ETF | 0.03% | 1 share (~$550) | $1.5T+ |
| IVV | iShares | ETF | 0.03% | 1 share (~$600) | $550B+ |
| VFIAX | Vanguard | Mutual Fund | 0.04% | $3,000 | $450B+ |
| SPY | SPDR | ETF | 0.09% | 1 share (~$600) | $600B+ |
AUM = Assets Under Management. FNILX tracks a proprietary Fidelity index (not S&P 500 directly). SPY (0.09% ER) is the original 1993 ETF and carries the deepest options market — making it the default for traders writing covered calls or buying puts. For long-term buy-and-hold investors, IVV or VOO deliver identical S&P 500 exposure at one-third the cost.
10-Year Annualized Performance
| Fund | 10-Year | 5-Year | 1-Year |
|---|---|---|---|
| FXAIX | ~15.5% | ~15.7% | ~15.8% |
| VOO | ~15.6% | ~15.7% | ~15.7% |
| S&P 500 Index | ~16.0% | ~15.8% | ~16.0% |
Returns as of early 2026. Slight differences reflect expense ratios and minor tracking variation.
Total US Market Funds
Total market funds hold the entire US stock market — roughly 3,500–4,000 stocks including small- and mid-cap companies the S&P 500 misses. Many investors prefer total market funds for broader diversification.
| Fund | Index Tracked | Holdings | Expense Ratio | Minimum |
|---|---|---|---|---|
| FZROX | Fidelity US Total Market | ~2,800 | 0.00% | $0 |
| FSKAX | Dow Jones US Total Market | ~3,800 | 0.015% | $0 |
| VTI | CRSP US Total Market | ~3,600 | 0.03% | 1 share (~$290) |
| SWTSX | Dow Jones US Total Market | ~3,400 | 0.03% | $0 |
| ITOT | S&P Total Market | ~3,400 | 0.03% | 1 share (~$130) |
| VTSAX | CRSP US Total Market | ~3,600 | 0.04% | $3,000 |
S&P 500 vs. Total Market
S&P 500 Funds
Cover ~80% of US market cap. More widely available in 401(k) plans, lower index turnover, and slightly less small-cap exposure. Historical performance nearly identical to total market.
Total Market Funds
Cover ~100% of US market cap (~3,500–4,000 stocks). Include small- and mid-cap companies for broader diversification and slightly less mega-cap concentration.
Correlation: 0.99+. Over 10–20 years, performance differences between S&P 500 and total market funds are minimal. Pick whichever is available — consistency matters more than the specific fund.
International Funds
International stock funds provide exposure to companies outside the US. A common allocation guideline is 70–80% US / 20–30% international; global market weights are approximately 60% US / 40% ex-US.
| Fund | Coverage | Holdings | Expense Ratio | Minimum |
|---|---|---|---|---|
| FZILX | Total International (ex-US) | ~2,300 | 0.00% | $0 |
| FTIHX | Total International (ex-US) | ~5,000 | 0.06% | $0 |
| SWISX | Developed Only (MSCI EAFE) | ~1,500 | 0.06% | $0 |
| IXUS | Total International (ex-US) | ~4,400 | 0.07% | 1 share (~$70) |
| VXUS | Total International (ex-US) | ~8,500 | 0.08% | 1 share (~$65) |
| VTIAX | Total International (ex-US) | ~8,500 | 0.12% | $3,000 |
Developed vs. Emerging Markets
Developed Markets (~75–80%)
Japan, UK, France, Germany, Canada, Australia, Switzerland. More stable economies with better shareholder protections, but lower growth potential.
Emerging Markets (~20–25%)
China, India, Taiwan, Brazil, South Korea, Mexico. Higher growth potential with more volatility, political risk, and currency risk.
Schwab gap: SWISX covers developed markets only (MSCI EAFE) and excludes emerging markets. Schwab investors wanting total international exposure can pair SWISX with SCHE (Schwab Emerging Markets ETF, 0.11% ER).
Building a Portfolio
The classic “three-fund portfolio” uses a US stock fund, an international stock fund, and a bond fund. Adjust the bond allocation based on age and risk tolerance.
Three-Fund Portfolio by Brokerage
| Allocation | Fidelity | Vanguard | Schwab |
|---|---|---|---|
| US Stocks (60%) | FSKAX or FZROX | VTI or VTSAX | SWTSX |
| International (20%) | FTIHX or FZILX | VXUS or VTIAX | SWISX |
| Bonds (20%) | FXNAX | BND or VBTLX | SWAGX |
ETF vs. Mutual Fund
Both ETFs and mutual funds can track the same index at nearly identical cost. The wrapper you choose affects tax efficiency, how you invest, and which account type benefits most.
| Feature | ETF | Mutual Fund |
|---|---|---|
| Tax efficiency | Higher (in-kind redemptions avoid cap gains) | Lower (except Vanguard’s dual-class structure) |
| Trading | Intraday at market price | End-of-day at NAV |
| Fractional shares | Broker-dependent | Buy exact dollar amounts |
| Auto-investing | Limited | Easy automatic contributions |
| Expense ratios | Often 0.01% lower | Slightly higher |
| Best for | Taxable accounts | Retirement accounts (IRA, 401k) |
Vanguard’s unique structure: Vanguard mutual funds share a class structure with their ETFs, allowing even the mutual fund versions (VTSAX, VTIAX) to minimize capital gains distributions — a tax advantage other providers don’t offer.
Sources
- 1.Fidelity — Fund Fact Sheets (FXAIX, FSKAX, FTIHX, FZROX, FNILX)
- 2.Vanguard — ETF & Mutual Fund Product Pages (VOO, VTI, VXUS, BND)
- 3.Schwab Asset Management — Fund Pages (SWPPX, SWTSX, SWISX, SWAGX)
- 4.iShares by BlackRock — Core ETF Product Pages (IVV, ITOT, IXUS, AGG)
- 5.Bogleheads — Three-Fund Portfolio
- 6.Morningstar — Fund Fee Study & Fund Comparison Tools
This content is for educational and informational purposes only and does not constitute financial, tax, or legal advice. Consult a qualified professional for guidance tailored to your situation.
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