VTI vs VOO: Which Vanguard ETF Should You Actually Own?
VTI holds every publicly traded US stock. VOO holds only the S&P 500. Both charge 0.03%, both are issued by Vanguard, and yet Bogleheads have debated this exact matchup for over a decade. Here is what actually differs, what doesn't, and how to pick without over-thinking it.
What each ETF actually tracks
VOO (Vanguard S&P 500 ETF) tracks the S&P 500 - roughly 500 of the largest US companies, weighted by market capitalization. Inclusion is decided by an S&P Dow Jones committee, not a mechanical rule, and the index is rebalanced quarterly.
VTI (Vanguard Total Stock Market ETF) tracks the CRSP US Total Market Index - essentially every US stock that meets basic liquidity screens, from Apple down to micro-cap names most investors have never heard of. As of 2026 that is around 3,700 to 4,100 holdings depending on the quarter.
Head-to-head: the numbers that actually matter
| Metric | VTI | VOO |
|---|---|---|
| Issuer | Vanguard | Vanguard |
| Index tracked | CRSP US Total Market | S&P 500 |
| Holdings | ~3,700-4,100 | ~503 |
| Expense ratio | 0.03% | 0.03% |
| 30-day SEC yield (2026) | ~1.35% | ~1.30% |
| Assets under management | $1.8T+ | $1.5T+ |
| Bid-ask spread (typical) | 1 cent | 1 cent |
| Small/mid-cap exposure | ~12-15% of weight | 0% |
| Top-10 concentration | ~30% | ~35% |
| Available as mutual fund | VTSAX (0.04%) | VFIAX (0.04%) |
Fees are identical. Yields are within a rounding error. Trading costs are identical. The only real functional difference is the universe of stocks each one covers, and how that changes concentration at the top.
The performance gap: how big is it really?
Over the ten years ending December 2025, VTI returned roughly 11.9% annualized and VOO returned roughly 12.4% annualized. That is a 50 basis point per year gap in favour of VOO - not because the S&P 500 index is structurally better, but because large-cap growth stocks led the market for that specific decade.
Over rolling 20-year windows going back to 1990 (using the underlying indexes), the average annualized gap between total market and S&P 500 is around 20 basis points, and the direction flips regularly. Small caps outperformed large caps in the early 2000s and again in 2003 to 2006. Large caps have led since 2014. Nobody has consistently called those regime changes in advance.
How to actually pick between them
Which one fits your setup
- Pick VTI if this is your only US equity holding and you want one-decision exposure to the whole US market.
- Pick VOO if you already hold a US small-cap fund (VB, IJR, AVUV) and want to avoid overlap.
- Pick VOO if your workplace 401(k) offers a low-cost S&P 500 fund and you want to match it across your other accounts for simplicity.
- Pick either one for automatic contributions - the 0.05% long-term performance difference will never justify picking the 'right' one based on this decade's numbers.
- Do not hold both in the same account: the small-cap tilt gets diluted, and you now have two lines to rebalance instead of one.
Where each one fits in a portfolio
VTI-first setup
- One-fund US core, no gaps
- Owns the next Google before it joins the S&P
- Slight small-cap and factor tilt built in
- Pairs cleanly with VXUS for total world exposure
- Best for hands-off contributors
VOO-first setup
- Matches most 401(k) menus
- Cleaner when you want to bolt on AVUV or IJR
- Fractionally lower expense drag from mid-cap churn
- Slightly higher yield in a rising-dividend environment
- Best when you want to control small-cap weight explicitly
What about Canadian investors?
Canadians can hold VTI or VOO directly, but the round-trip FX cost of buying them in a CAD account eats about 100 to 150 basis points unless you Norbert's-gambit the conversion. In a TFSA, US-listed ETFs also lose 15% of dividend distributions to non-recoverable withholding tax.
Canadian equivalents keep the exposure without the paperwork: VUN (Vanguard Total US Market, 0.16%) mirrors VTI, and VFV (Vanguard S&P 500 Index ETF, 0.09%) or ZSP (BMO S&P 500, 0.09%) mirror VOO. The MER premium versus the US-listed originals is 5 to 13 basis points - usually cheaper than the FX cost of doing it yourself.
Account placement: where to actually hold it
| Account | Best choice | Why |
|---|---|---|
| US Roth IRA / traditional IRA | VTI or VOO | No withholding tax, no FX friction. Pick the one that fits your other holdings. |
| US 401(k) / 403(b) | Whichever the plan offers | Do not chase VTI if your plan only has an S&P 500 fund - the fee difference is trivial. |
| US taxable brokerage | VTI (marginally) | VTI turns over less than the S&P 500 rebalances, so it is slightly more tax-efficient. |
| Canadian RRSP | VTI directly | US-Canada tax treaty exempts RRSPs from the 15% dividend withholding. |
| Canadian TFSA / non-registered | VUN or VFV | US-listed ETFs bleed 15% of dividends to withholding tax that you cannot recover. |
Can you hold both VTI and VOO?
Technically yes, but it defeats the point of each one. VOO's holdings are already inside VTI - stacking them just dilutes the small and mid-cap tilt that made VTI different in the first place. If you want to hold the S&P 500 plus extra small-cap exposure, the cleaner build is VOO + AVUV or VOO + IJR, where you control the weighting explicitly.
There is also a wash sale angle: VTI and VOO are similar enough that some tax advisors treat them as substantially identical for wash sale purposes, though the IRS has never issued formal guidance. Tax-loss harvesting between VTI and IVV (iShares S&P 500) or VTI and SPLG (SPDR Portfolio S&P 500) is generally considered safer than harvesting between VTI and VOO.
The bottom line
VTI and VOO are the same fee, the same issuer, and about 85% the same portfolio by weight. The choice is philosophical, not financial: do you want to own the whole US market, or do you want to own only the companies large enough to be voted into the S&P 500?
For most investors setting up their first US equity holding, VTI is the slightly more defensible default - it removes one decision (which small-cap fund to add) and never leaves you exposed to the reverse of the last decade, where small caps lead. But if VOO is already in your 401(k), or you have an AVUV or IJR sleeve you like, staying with VOO costs you essentially nothing.
Frequently asked questions
Which has performed better historically, VTI or VOO?
Over the last 10 years (through 2025) VOO edged out VTI by roughly 50 basis points annualized, driven by large-cap growth leadership. Over rolling 20-year windows the gap averages around 20 basis points and the winner flips depending on whether small caps or large caps are in favour. Neither has a structural advantage over the long run.
Is VTI more diversified than VOO?
Yes, technically. VTI holds around 3,700 to 4,100 US stocks vs about 503 for VOO. But the extra 3,600 small and mid-cap names only make up 12 to 15 percent of VTI's weight, so the two ETFs move together roughly 99 percent of the time on any given day.
Should I switch from VOO to VTI (or vice versa)?
Not in a taxable account - the capital gains you would trigger will almost always cost more than any long-run performance difference between the two. In a Roth IRA or 401(k) rollover where switching is free, pick whichever fits your other holdings best and stop optimizing.
Can Canadians buy VTI and VOO in a TFSA?
You can buy them, but you shouldn't. US-listed ETFs held in a TFSA lose 15 percent of dividend distributions to non-recoverable withholding tax. The Canadian-listed equivalents VUN (mirrors VTI) and VFV (mirrors VOO) recover that same withholding at the fund level.
What is the Canadian equivalent of VTI?
VUN (Vanguard US Total Market Index ETF) - it holds the same underlying index basket as VTI but is CAD-listed on the TSX. MER is 0.16% vs VTI's 0.03%, but avoiding the FX round-trip usually more than pays for the difference.
Are VTI and VOO wash sale substitutes for tax-loss harvesting?
There is no IRS ruling, but many advisors consider them substantially identical because VOO's holdings are entirely inside VTI. Safer pairings for a 30-day harvest window are VTI to IVV (iShares S&P 500), VTI to SPLG (SPDR Portfolio S&P 500), or VOO to SCHB (Schwab US Broad Market).