$500 a Month in the Nasdaq vs the S&P 500 Over 20 Years: Which Won?
Most people who automate retirement contributions buy a broad S&P 500 fund and never think about it again. It is the default, and it is a good one. But over the last 20 years, the Nasdaq-100 quietly turned the same monthly habit into nearly twice the money. Here is what $500 a month into each one actually produced.
Investing $500 a month for 20 years means $120,500 in total contributions (241 monthly buys). Put into the Nasdaq-100 via QQQ, that plan grew to approximately $1,047,900. The same plan into the S&P 500 via SPY reached approximately $561,100. The Nasdaq nearly doubled the index.
The 20-Year Result
| $500/month for 20 years | Nasdaq-100 (QQQ) | S&P 500 (SPY) |
|---|---|---|
| Total contributed | $120,500 | $120,500 |
| Ending value | $1,047,900 | $561,100 |
| Growth multiple | 8.7x | 4.7x |
How the Gap Opened Up
The two plans tracked closely for the first decade. The Nasdaq's advantage came almost entirely in the second half, as megacap tech and the AI trade pulled the index away.
| Years in | Contributed | QQQ value | SPY value |
|---|---|---|---|
| 5 | $30,000 | $42,100 | $36,400 |
| 10 | $60,000 | $121,900 | $100,800 |
| 15 | $90,000 | $466,300 | $272,200 |
| 20 | $120,500 | $1,047,900 | $561,100 |
At the 10-year mark the two were within about $21,000 of each other. By year 20 the gap had grown to roughly $487,000. The divergence is recent and concentrated, which matters for what it does and does not tell you about the future.
The Volatility Was Real
The Nasdaq-100 did not deliver that result smoothly. It is a more concentrated, more tech-heavy index, and it fell harder in every major drawdown of the period. On a monthly-close basis, both indexes lost roughly half their value during the 2008 financial crisis. But the Nasdaq's swings in 2000 to 2002, in 2018, and in 2022 were consistently sharper than the S&P 500's. The reason the higher-volatility index won is the same reason it could have lost: it is a bigger bet on a narrower slice of the market.
Dollar-cost averaging actually softened this. Buying every month meant scooping up extra shares during the 2008 and 2022 declines, which is a large part of why the ending values are as high as they are. An investor who panicked and stopped contributing during those drops would have captured far less of the recovery.
One Important Caveat: Dividends
These figures use split-adjusted closing prices and do not include dividends. That understates both totals, but it understates the S&P 500 more, because SPY has historically paid a higher dividend yield than QQQ (roughly 1.5% versus under 1%). Reinvested dividends would narrow the gap somewhat, though not enough to change the order of finish. The Nasdaq still wins over this particular 20-year window. It just wins by a bit less than the price-only numbers suggest.
The Bottom Line
Over the last 20 years, $500 a month in the Nasdaq-100 grew to about $1,047,900 versus about $561,100 for the S&P 500, nearly double. The catch is that this is one specific, tech-led window, and the Nasdaq took sharper losses along the way to get there. Past outperformance of a concentrated index is not a promise of future outperformance, and the higher return came strapped to higher volatility. For most people the right takeaway is not Nasdaq over S&P 500, it is that consistent monthly investing over decades is what did the heavy lifting in both columns.
Compare this with $500 a month in the S&P 500 for 30 years and the case for lump sum vs dollar-cost averaging.