MMK vs SPY
State Street Prime Money Market ETF vs State Street SPDR S&P 500 ETF Trust
Which is better, MMK or SPY?
SPY costs less.
SPY has a lower expense ratio.
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 | MMK | SPY |
|---|---|---|
| Expense Ratio | 0.18% | 0.09%Best |
| AUM | $29M | $811.2B |
| Dividend Yield | 1.68% | 0.98% |
| Holdings | 69 | 1,515 |
| YTD Return | +2.33% | +13.54%Best |
| 1Y Return | - | +16.25% |
| 3Y Return (annualized) | - | +23.72% |
| 5Y Return (annualized) | - | +13.95% |
| Fund Family | State Street Investment Management | State Street Investment Management |
| Category | Money Market | Equity |
| Style | - | Large Cap Blend |
| Inception | Feb 10, 2026 | Jan 22, 1993 |
Not shown on this pair: Volatility (annualized), Max Drawdown, $10,000 over the window, Top 10 Weight.
MMK vs SPY 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.
MMK vs SPY Performance
State Street Prime Money Market ETF (MMK) is an ETF from State Street Investment Management and State Street SPDR S&P 500 ETF Trust (SPY) is an ETF from State Street Investment Management. Year to date, MMK is up 2.33% versus a gain of 13.54% for SPY.
Past performance does not guarantee future results.
Fees and Cost Over Time
MMK charges 0.18% per year while SPY charges 0.09%. On a $10,000 position that is $18 vs $9 annually, a gap of $9 per year that compounds over a long holding period. On income, MMK currently yields 1.68% against 0.98% for SPY.
Holdings Overlap
We hold position weights for 1 holding in MMK and 504 in SPY, totalling 1.2% and 99.8% of the two funds. The two books name no position in common, so there is no overlap percentage to show.
0 positions in common, counted across the 1 positions we hold weights for in MMK and 504 in SPY, against full books of 69 and 1,515.
You are not choosing between two funds in isolation.
Whichever of MMK and SPY you pick has to sit alongside everything else you own. Add the rest and see what the combination actually holds.
Free for up to 10 holdings. No account needed.
Frequently Asked Questions
Which is cheaper, MMK or SPY?
MMK has an expense ratio of 0.18% while SPY charges 0.09%. SPY is the cheaper option, by $9 a year on a $10,000 investment.
Which pays a higher dividend, MMK or SPY?
MMK yields 1.68% while SPY yields 0.98%, so MMK currently pays the higher dividend yield.
Is SPY better than MMK?
SPY has a lower expense ratio. Which one suits a particular account depends on what it is for. This is information, not a recommendation.