If you want to own the entire US stock market in a single fund at the lowest possible cost, two options dominate the conversation: the Vanguard Total Stock Market ETF (VTI) and the Fidelity ZERO Total Market Index Fund (FZROX). Both track the total US equity market. Both deliver near-identical returns. And together they represent the two most cost-efficient ways to invest in the broadest possible slice of the American economy. The differences between them are real but narrow — and understanding them will help you make the right choice for your specific situation.
What Is a Total Market Fund?
A total market fund differs from an S&P 500 fund in one important way: it includes not just the 500 largest companies but also mid-cap and small-cap stocks — giving investors exposure to thousands of US companies rather than just the largest 500.
VTI tracks the CRSP US Total Market Index and holds approximately 3,700 stocks as of May 2026. FZROX tracks Fidelity’s proprietary Fidelity US Total Investable Market Index and holds approximately 2,600 stocks. Both include large-cap, mid-cap, and small-cap stocks. FZROX omits some of the smallest micro-cap names that VTI includes, which is part of how Fidelity achieves its zero expense ratio — fewer small, illiquid positions reduce trading costs.
In practice the difference in coverage matters very little. The large-cap stocks that make up the overwhelming majority of both funds’ weight are identical — Apple, Nvidia, Microsoft, Amazon, and Alphabet sit at the top of both. The small and micro-cap names that FZROX omits represent a tiny fraction of total market value.
Side-by-Side Comparison
| VTI | FZROX | |
|---|---|---|
| Issuer | Vanguard | Fidelity |
| Fund type | ETF | Mutual fund |
| Expense ratio | 0.03% | 0.00% |
| Annual cost per $10,000 | $3.00 | $0.00 |
| Number of holdings | ~3,700 | ~2,600 |
| Index tracked | CRSP US Total Market | Fidelity US Total Investable Market |
| 5-year annualized return | 12.77% | 13.01% |
| 1-year return | 31.12% | 31.27% |
| Dividend yield (TTM) | ~1.02% | ~0.93% |
| Correlation | 1.00 | 1.00 |
| Brokerage availability | Any broker | Fidelity only |
| Tradable intraday | Yes | No |
| Tax efficiency | High (ETF structure) | Moderate (mutual fund) |
| Portability | Full — transfers freely | None — must sell to leave Fidelity |
Where FZROX Wins
Expense ratio. FZROX charges 0.00% — literally nothing. VTI charges 0.03%, which costs $3 per year per $10,000 invested. On a $100,000 portfolio, VTI costs $30 per year versus $0 for FZROX. On a $500,000 portfolio, that gap grows to $150 per year. Over 30 years of compounding, the difference is real but modest — not the headline advantage it might appear to be, since we are comparing $0 to $3 per $10,000 rather than to something meaningfully more expensive.
Recent return performance. Over the past five years, FZROX has delivered an annualized average return of 13.01% compared to VTI’s 12.77% — a gap of 0.24 percentage points. Over the past year, FZROX returned 31.27% versus VTI’s 31.12%. The performance edge is consistent and attributable primarily to the expense ratio advantage and the slightly different index composition. The correlation between the two is 1.00, meaning they move in near-perfect lockstep.
No minimum investment at Fidelity. FZROX requires no minimum investment and can be purchased in any dollar amount at Fidelity, making it ideal for investors starting with small, regular contributions who want to deploy every dollar without being constrained by share prices.
Where VTI Wins
Portability. This is VTI’s most significant practical advantage and the factor most likely to determine the right choice for your situation. VTI is an ETF that can be held at any brokerage — Fidelity, Schwab, TD Ameritrade, Robinhood, Interactive Brokers, or any other platform — and transferred between brokerages at no cost without selling. FZROX is a Fidelity-proprietary mutual fund that can only be held at Fidelity. If you ever want to move your account to another brokerage, you must sell your FZROX shares first. In a taxable account, that sale triggers a capital gains tax event — potentially costing significantly more than the $3 annual savings per $10,000 that FZROX’s zero expense ratio provides.
Tax efficiency. VTI’s ETF structure gives it the same capital gains distribution advantage discussed in the ETF vs index fund comparison. Because of the in-kind creation and redemption mechanism, VTI rarely distributes taxable capital gains to shareholders. FZROX, as a mutual fund, can distribute capital gains when other investors sell their shares — a relevant consideration for taxable brokerage accounts, though less significant inside IRAs and 401(k)s where taxes are deferred.
Broader small-cap coverage. VTI’s 3,700 holdings include a fuller spectrum of small and micro-cap stocks than FZROX’s 2,600. Small-cap stocks have historically provided higher long-term returns than large-caps in exchange for higher volatility. The practical impact of this difference on returns has been negligible between these two funds historically, but investors who specifically want maximum market breadth will find VTI’s coverage more complete.
Longer track record. VTI launched in 2001 and has 25 years of operational history. FZROX launched in 2018 and has a track record of approximately eight years. For investors who place weight on long-term fund history and the institutional experience behind it, VTI’s additional 17 years of data provides more comfort.
The Real Decision: Which Brokerage Are You Using?
The most practical way to choose between VTI and FZROX is not to compare their returns or expense ratios in isolation — it is to answer one question: where do you hold your account, and do you intend to stay there long term?
If you are at Fidelity and plan to remain at Fidelity for the foreseeable future — particularly in a tax-advantaged account like a Roth IRA or traditional IRA where portability and capital gains taxes are not relevant — FZROX is the rational choice. The zero expense ratio delivers a genuine, if modest, cost advantage and there is no practical downside inside a Fidelity retirement account.
If you are at any other brokerage, or if there is any meaningful chance you will want to switch brokerages in the future, VTI at 0.03% is the better choice. Its portability, tax efficiency, and ETF structure make it a more flexible long-term holding, and the $3 per $10,000 annual cost is genuinely inconsequential relative to the flexibility it preserves.
If you are a Fidelity customer investing in a taxable brokerage account with a long time horizon, the portability consideration is worth taking seriously. The tax cost of selling FZROX to transfer to another brokerage could easily exceed decades of expense ratio savings in a single transaction.
Final Thoughts
VTI and FZROX are functionally near-identical investments that will produce near-identical long-term outcomes for investors who stay in their chosen brokerage. The performance difference is within 0.25% annually. The cost difference is $3 per $10,000 per year. The meaningful differences — portability, tax efficiency, and brokerage dependency — are structural rather than performance-related. Choose based on where you invest and how long you plan to stay there, not on the headline expense ratio difference.
Investment Disclaimer: This article is for informational purposes only and does not constitute investment, financial, or tax advice. Investing involves risk, including the possible loss of principal. Past performance does not guarantee future results. Consult a qualified financial advisor before making any investment decisions. FinanceRP may earn a commission through affiliate links on this page, at no extra cost to you.
Pau Rebollo is an independent investor and technology writer covering personal finance, passive investing, and AI tools. He has hands-on experience in equity markets and cryptocurrency, and has founded multiple ventures at the intersection of business and technology. Pau approaches financial topics from a practical perspective — cutting through the noise to deliver clear, data-backed information for everyday investors and tech-savvy readers. All content on this site is for informational purposes only and does not constitute financial advice.