MMID vs VOO
MFS Active Mid Cap ETF vs Vanguard S&P 500 ETF
Which is better, MMID or VOO?
Mid Cap Blend against Large Cap Blend.
VOO has a lower expense ratio. VOO led over 1Y. MMID is less concentrated, with 15.2% of the fund in its ten largest positions against 36.4%.
MarketXLS is not an investment adviser. This comparison is generated automatically from market data and is for information only. A Best mark means the better reading on that one measure, not a recommendation to buy.
Side-by-Side Comparison
| Metric | MMID | VOO |
|---|---|---|
| Expense Ratio | 0.59% | 0.03%Best |
| AUM | $36M | $997.4B |
| Dividend Yield | 0.68% | 1.04% |
| Holdings | 106 | 509 |
| YTD Return | +5.59% | +11.55%Best |
| 1Y Return | +7.01% | +17.54%Best |
| 3Y Return (annualized) | - | +20.71% |
| 5Y Return (annualized) | - | +12.80% |
| Volatility (annualized) | 9.9%Best | 13.4% |
| Top 10 Weight | 15.2%Best | 36.4% |
| Fund Family | MFS Investment Management | Vanguard (US) |
| Category | Equity | Equity |
| Style | Mid Cap Blend | Large Cap Blend |
| Inception | Sep 24, 2025 | Sep 7, 2010 |
Not shown on this pair: Max Drawdown, $10,000 over the window.
MMID vs VOO growth
Month-end closes. Both lines start at 0% in the first month shown, so the gap between them is the difference in growth across that window. The full view is available from the range buttons; it is not the opening view here because over the whole period one of these two funds moves so much further than the other that its line would sit flat on the axis.
MMID vs VOO Performance
MFS Active Mid Cap ETF (MMID) is an ETF from MFS Investment Management and Vanguard S&P 500 ETF (VOO) is an ETF from Vanguard (US). Over the past year MMID returned +7.01% while VOO returned +17.54%. Year to date, MMID is up 5.59% versus a gain of 11.55% for VOO.
Past performance does not guarantee future results.
Risk: Volatility and Drawdowns
VOO has been the more volatile fund, with annualized monthly volatility of 13.4% compared with 9.9% for MMID. Lower volatility generally means a smoother ride, though it often comes with lower long-run returns.
The two funds' monthly returns correlate at 0.54. They move together some of the time, and apart the rest.
Fees and Cost Over Time
MMID charges 0.59% per year while VOO charges 0.03%. On a $10,000 position that is $59 vs $3 annually, a gap of $56 per year that compounds over a long holding period. On income, MMID currently yields 0.68% against 1.04% for VOO.
Holdings Overlap
56.8% of MMID's money is in holdings VOO also owns. 2.8% of VOO's money is in holdings MMID also owns.
The two portfolios partly overlap.
The two holdings books were reported 49 days apart, MMID as of Aug 18, 2026 and VOO as of Jun 30, 2026, so some of the difference between them is the time between the two reports rather than the funds.
55 positions in common, counted across the 106 positions we hold weights for in MMID and 505 in VOO, against full books of 106 and 509.
What only one of them owns
Our book lists 441 positions for VOO that do not appear in our book for MMID (96.7% of the fund), and 40 for MMID that do not appear in VOO (35.0%).
Some of those will be the same company recorded under a different code in one of the two books, so the real difference in what you would own is no larger than this and may be smaller. We do not name the individual positions here for that reason.
Top Shared Holdings
| Stock | Weight in MMID | Weight in VOO | Difference |
|---|---|---|---|
| GPNGlobal Payments Inc. | 1.73% | 0.02% | 1.71% |
| FANGDiamondback Energy Inc. | 1.66% | 0.05% | 1.61% |
| GWWWw Grainger Inc. | 1.54% | 0.09% | 1.45% |
| WATWaters Corp. | 1.52% | 0.06% | 1.46% |
| WABWestinghouse Air Brake Technologies Corp. | 1.50% | 0.07% | 1.43% |
| BDXBecton Dickinson And Co. | 1.45% | 0.06% | 1.39% |
| STESteris Plc | 1.43% | 0.03% | 1.40% |
| MTBM&t Bank Corp. | 1.38% | 0.05% | 1.33% |
| AAgilent Tech In 3.2 10/22 | 1.36% | 0.06% | 1.30% |
| VLOValero Energy Corp. | 1.27% | 0.12% | 1.15% |
56.8% of MMID is already inside VOO.
You probably hold more than these two. Add the rest and see how much of the whole book is the same companies twice.
Free for up to 10 holdings. No account needed.
Frequently Asked Questions
Which is cheaper, MMID or VOO?
MMID has an expense ratio of 0.59% while VOO charges 0.03%. VOO is the cheaper option, by $56 a year on a $10,000 investment.
Which performed better, MMID or VOO?
Over the past year MMID returned +7.01% vs +17.54% for VOO, so VOO leads on 1-year performance. Past performance does not guarantee future results. This is information, not a recommendation.
Which is riskier, MMID or VOO?
VOO has been the more volatile fund at 13.4% annualized versus 9.9% for MMID.
Should I hold both MMID and VOO?
MMID and VOO have a monthly-return correlation of 0.54, so their returns are far enough apart for the mix to behave differently from either one alone. This is information, not a recommendation.
What is the holdings overlap between MMID and VOO?
56.8% of MMID's money is in holdings VOO also owns. 2.8% of VOO's is in holdings MMID also owns. They hold 55 positions in common, counted across the 106 positions we hold weights for in MMID and 505 in VOO.
Which pays a higher dividend, MMID or VOO?
MMID yields 0.68% while VOO yields 1.04%, so VOO currently pays the higher dividend yield.
Is VOO better than MMID?
VOO has a lower expense ratio. VOO led over 1Y. MMID is less concentrated, with 15.2% of the fund in its ten largest positions against 36.4%. Which one suits a particular account depends on what it is for. This is information, not a recommendation.