VOO vs VTI: Which ETF Should You Buy

VOO and VTI are two of the most widely held ETFs in the world. VOO tracks the S&P 500 — 500 large-cap U.S. companies. VTI tracks the entire U.S. stock market — roughly 3,700 companies including all the large caps plus mid-cap and small-cap stocks. Both charge 0.03% per year. Both are offered by Vanguard.

The question of which one to buy generates an enormous amount of debate online. The honest answer is that the difference is trivially small and the debate is mostly a distraction. But understanding why they are nearly identical — and the specific situations where the difference actually matters — is worth your time.

The Core Difference

VOO holds the companies in the S&P 500 index as selected by the S&P Dow Jones Indices committee. There are roughly 503 holdings (some companies have multiple share classes). The index targets large-cap U.S. stocks and uses a float-adjusted market cap weighting, meaning the biggest companies — Apple, Microsoft, Nvidia, Amazon, Meta, Alphabet — get the largest weights.

VTI holds essentially all publicly traded U.S. stocks, weighted by market cap. The current holdings count is approximately 3,600–3,700 companies. Because U.S. markets are top-heavy, the large caps that dominate VOO also dominate VTI.

Here is the key insight: the top 500 companies in the U.S. market account for roughly 82–85% of total U.S. market capitalization. So VTI is approximately 82–85% identical to VOO by market cap weight. The extra ~3,200 small and mid-cap companies in VTI represent the remaining 15–18% of the portfolio.

The actual overlap, by weight:

	VOO	VTI
Large-cap weight	~100%	~82%
Mid-cap weight	0%	~13%
Small-cap weight	0%	~5%
Number of holdings	~503	~3,700
Expense ratio	0.03%	0.03%

Historical Performance Comparison

This is where the “which is better” debate gets resolved by data.

Over the past 10 years (2016–2025), VTI has outperformed VOO by roughly 0.0–0.2% per year depending on the exact window measured. That is not a typo — the difference is less than 0.2% annually, and it flips direction depending on whether small and mid-cap stocks are outperforming or underperforming large caps.

In years when large-cap tech dominates (2019, 2020, 2023, 2024), VOO slightly outperforms VTI because VOO is more concentrated in those mega-cap winners. In years when small and mid-caps recover (2021, parts of 2016), VTI slightly outperforms VOO.

Approximate annualized returns (10-year through 2025):

	VOO	VTI
10-year annualized return	~13.0%	~12.8%
5-year annualized return	~15.4%	~15.3%
3-year annualized return	~9.7%	~9.5%
Expense ratio	0.03%	0.03%
Correlation to each other	0.99	0.99

The correlation of 0.99 is the most important number. On any given day, week, or year, VOO and VTI move in essentially the same direction by essentially the same magnitude. You will not find meaningful diversification benefit by owning both.

When VTI’s Broader Exposure Actually Matters

There are real-world scenarios where the extra small and mid-cap exposure in VTI creates a meaningful difference, even if the historical data suggests otherwise over recent history.

Valuation cycles: Small and mid-cap stocks tend to trade at lower valuations relative to earnings than mega-cap tech. When market leadership rotates away from large caps — as it did from 2000–2006 after the dot-com bubble — small and mid-caps significantly outperform. VTI provides automatic participation in that rotation without requiring you to predict when it happens.

Economic recovery cycles: Small and mid-cap stocks are more domestically oriented and tend to outperform early in economic recovery cycles when credit is loosening and domestic growth is accelerating. If you believe the next decade looks more like the 2000s (broad value leadership) than the 2010s (mega-cap growth leadership), VTI is the better total-market expression of that view.

Pure diversification principle: If you believe in owning the market, VTI is a more complete expression of that belief. The S&P 500 is technically an actively managed index — a committee decides which 500 companies qualify. VTI follows a rules-based methodology that captures essentially everything.

The counterargument (VOO’s case): VOO’s concentration in mega-cap quality companies has been a feature, not a bug, in the era of technology platform businesses with winner-take-most economics. If you believe that structural advantage persists, the S&P 500’s implicit quality tilt is useful.

Expense Ratio Deep Dive

Both ETFs charge 0.03% per year — an expense ratio that was essentially inconceivable when Vanguard launched its first index fund in 1976. At this price level, the difference between them is zero.

For context: on a $100,000 investment held for 30 years at 10% gross returns:

• At 0.03% expense ratio: you keep approximately $1,725,000
• At 1.00% expense ratio: you keep approximately $1,326,000
• The cost of the extra 0.97%: roughly $399,000

This is why expense ratios matter. At 0.03% vs 0.03%, the question of “VOO or VTI” is entirely about investment strategy and holdings composition — the cost is identical.

If you are comparing Vanguard ETFs to comparable offerings from iShares or Schwab, the comparison also holds:

• iShares Core S&P 500 (IVV): 0.03%
• iShares Core S&P Total U.S. Market (ITOT): 0.03%
• Schwab U.S. Broad Market (SCHB): 0.03%
• Schwab U.S. Large-Cap (SCHX): 0.03%

The entire category has converged to zero effective cost. Fund selection at this level is entirely about composition, not fees.

Tax Efficiency: Is One More Tax-Efficient?

Both VOO and VTI are highly tax-efficient in a taxable account, because:

1. Both use Vanguard’s patented ETF/mutual fund share class structure, which allows the ETF to offload low-basis shares in-kind to authorized participants, avoiding capital gains distributions. This patent expired in 2023, but Vanguard’s structure still minimizes taxable distributions.

2. Both are passive index funds with low turnover. VOO and VTI have annual turnover rates of roughly 2–4%, generating minimal realized capital gains.

3. Neither has had a capital gains distribution in over a decade.

The difference between the two on tax efficiency is negligible. If you are in a taxable account making the VOO vs VTI decision, taxes are not the differentiating factor.

The one tax consideration: If you ever decide to switch from one to the other in a taxable account, you will trigger a taxable event on any unrealized gains. This is an argument for picking one and staying with it indefinitely — not a reason to choose one over the other.

Side-by-Side Stats

Metric	VOO	VTI
Index tracked	S&P 500	CRSP US Total Market
Holdings count	~503	~3,700
Expense ratio	0.03%	0.03%
AUM	~$600B+	~$450B+
Dividend yield (approx)	~1.2–1.4%	~1.2–1.4%
Large-cap weight	~100%	~82%
Mid-cap weight	0%	~13%
Small-cap weight	0%	~5%
Top 10 holdings weight	~33%	~27%
Correlation to each other	—	0.99
10-year annualized (approx)	~13.0%	~12.8%
Beta vs S&P 500	1.00	~1.01

The Verdict: Just Pick One

Here is the honest take: for the vast majority of investors, the choice between VOO and VTI is irrelevant to your financial outcome. The 0.1–0.2% annual performance difference is dominated by:

• How much you invest
• How consistently you invest (dollar-cost averaging discipline)
• Whether you stay invested during drawdowns
• Your asset allocation (stocks vs bonds)
• Your tax efficiency (account type, holding period)

None of those factors have anything to do with whether you bought VOO or VTI.

If you are starting from scratch and genuinely cannot decide:

Pick VTI. It is a broader expression of the U.S. market, it captures small and mid-cap upside in rotation cycles, and it requires no committee to decide what counts as “large enough” to be included. Total market is a cleaner philosophy.

If you already own one or the other in a taxable account:

Do not switch. The transaction cost — taxes on embedded gains — is a real, immediate cost. The performance difference is hypothetical and small. Switching VOO to VTI to be “more diversified” in a taxable account with large gains is almost certainly a net negative outcome.

If you own both:

You do not need both. You are not adding diversification — you are adding complexity for no return benefit. If you are in a taxable account with gains in both, hold both positions until you want to harvest losses or rebalance. If you are in a tax-advantaged account, consolidating into one is fine.

What About International Diversification?

One important note: neither VOO nor VTI provides international diversification. Both are 100% U.S. equity exposure. U.S. companies do generate significant international revenue (S&P 500 companies derive roughly 40% of revenue from outside the U.S.), but that is not the same as owning international stocks.

If you want true global market exposure, consider pairing either fund with an international ETF like VXUS (Vanguard Total International Stock), which covers developed and emerging markets outside the U.S. A common allocation for those who want global coverage is 60–70% VTI + 30–40% VXUS — this approximates global market cap weighting.

For a full introduction to how these funds fit into a complete portfolio, see how to build an investment portfolio and best index funds for beginners.

The Mutual Fund Equivalents

If you prefer mutual funds over ETFs (for example, to enable automatic investment of exact dollar amounts without fractional share constraints), the Vanguard equivalents are:

• VFIAX — Vanguard 500 Index Fund Admiral Shares (equivalent to VOO), 0.04% ER, $3,000 minimum
• VTSAX — Vanguard Total Stock Market Index Fund Admiral Shares (equivalent to VTI), 0.04% ER, $3,000 minimum

The slightly higher 0.04% expense ratio vs the ETF’s 0.03% reflects the administrative costs of the mutual fund structure. For most investors, the 0.01% difference is immaterial — the mutual fund form is convenient for automated investing.

Common Questions

Can I hold both VOO and VTI? Yes, but you gain no meaningful diversification. VTI already contains all 500 VOO holdings plus ~3,200 more. Owning both is roughly equivalent to owning a slightly overweighted version of VTI. Not harmful, just unnecessary.

Which is better in an IRA? Either works. In an IRA, there are no tax implications from dividends or eventual switching, so the choice is purely about investment thesis. Most financial planners recommend VTI or VTSAX for simplicity.

Does the dividend yield differ? The difference is trivial — typically within 0.1%. Both yield approximately 1.2–1.4% as of recent data, depending on the period. Neither is a meaningful income vehicle at these yields; both reinvest dividends efficiently.

Will small caps eventually outperform? Historically, small-cap stocks have had higher long-run returns with higher volatility — the “small-cap premium” documented in academic finance. Over the past 15 years, this premium largely disappeared as mega-cap technology dominated. Whether the premium returns is a genuine open debate. VTI gives you exposure to it if it does; VOO eliminates that exposure.

The Bottom Line

VOO and VTI are not meaningfully different investment choices for the vast majority of investors. The correlation is 0.99. The expense ratios are identical at 0.03%. The performance difference over any long period is under 0.2% annually — noise, not signal.

VTI is the slightly more philosophically complete total-market vehicle. VOO is the slightly simpler, more recognized large-cap exposure. Both are excellent. The far more important decision is whether you are investing consistently, in the right account types, with the right overall allocation — none of which has anything to do with the VOO vs VTI debate.

For more on building the full picture, see what is an ETF and best index funds for beginners.