The short answer is that Bitcoin can get there faster, but it is much less predictable. The S&P 500 offers a slower path that has a long record behind it. From 1928 to 2025 the index returned 10.02% a year, compounded, with dividends reinvested. At that rate, $500 a month reaches $1 million in about 30 years, and $1,000 a month gets there in about 23. Bitcoin has had years of much bigger gains. It also has a short history and deep crashes. On October 23, 2026 it traded about 35% below its all-time high. No reliable long-run return figure exists that you could plan around.
Where both markets stand in October 2026
- S&P 500: The index closed at a record 7,818.93 on October 6, 2026, its 28th record close of the year. On October 22 the Motley Fool put its 2026 gain at about 13%. It closed at 7,623.68 on October 23.
- Bitcoin: Fortune's daily tracker put Bitcoin at $81,546.37 at 7:15 a.m. ET on October 23, 2026. That was about 25.9% lower than a year earlier. The all-time high in the same tracker is $126,198.07, set on October 6, 2025. From that peak, the October 23 price is about 35% lower.
- Rates: The Federal Reserve raised its benchmark rate in September 2026, its first increase in more than three years. In early October the 10-year Treasury yield rose above 5.3%, its highest level since 2002 (as reported by the Motley Fool).
Over the past year, the index fund has gone up while Bitcoin has gone down. This is the latest example of a pattern that keeps repeating.
The S&P 500 path: slow compounding
What the long-run numbers say
Aswath Damodaran at NYU Stern keeps a widely used dataset of annual S&P 500 total returns, with dividends included:
| Period | Geometric (compound) average | Arithmetic average |
|---|---|---|
| 1928–2025 | 10.02% | 11.86% |
| 1976–2025 (50 years) | 11.92% | 13.17% |
| 2016–2025 (10 years) | 14.68% | 15.75% |
The compound average is the right figure for planning, because it is the rate your money actually grew at. The last decade ran well above the long-run figure, so it is a poor basis for planning. The index also had bad years: -36.55% in 2008 and -18.04% in 2022, on the same dataset.
Fees and why indexing is hard to beat
Vanguard's fact sheet lists the expense ratio of the Vanguard S&P 500 ETF (VOO) at 0.03%. At that rate, $10,000 invested costs about $3 a year. S&P Dow Jones Indices' SPIVA scorecard for year-end 2025 found that 79% of active large-cap U.S. equity funds trailed the S&P 500 in 2025, up from 65% in 2024.
The $1 million math
The table below is plain compounding arithmetic. It assumes a fixed annual return, a deposit at the end of each month, and no taxes, fees or inflation. Real returns arrive unevenly, and these results are not forecasts.
| Monthly deposit | 7% a year | 10% a year (1928–2025 average) | 14.68% a year (2016–2025 average) |
|---|---|---|---|
| $500 | ~37 years | ~30 years | ~23 years |
| $1,000 | ~28 years | ~23 years | ~18 years |
At 10%, $500 a month grows to about $100,000 after 10 years, $359,000 after 20 and $1.03 million after 30. Most of the final balance comes from the last ten years, which is why starting early matters more than any other input. The 7% column is there because inflation and costs cut what you actually earn below the headline return.
How long until your deposits reach $1 million?
Enter a monthly deposit, a fixed annual return and a number of years to see the ending balance under the article's compounding arithmetic.
| Monthly deposit | Fixed annual return, compounded | Years of monthly deposits | Ending balance before taxes, fees and inflation |
|---|---|---|---|
| 500 USD | 10 % | 30 years | 1,031,422 USD |
| 1,000 USD | 10 % | 23 years | 997,512 USD |
| 500 USD | 7 % | 37 years | 992,512 USD |
| 500 USD | 14.68 % | 23 years | 973,266 USD |
- The return is a fixed rate every year; real returns arrive unevenly, with years such as -36.55% in 2008 and -18.04% in 2022.
- Deposits are made at the end of each month, with no taxes, fees or inflation, as in the article's table.
- The result shows what happens if the entered rate repeats every year. It is not a forecast.
This is compounding arithmetic on your inputs only: it leaves out taxes, fees, inflation and uneven or negative years, and cannot project Bitcoin, which has no reliable long-run return to enter.
The Bitcoin path: faster in good years, no reliable average
What is known
- Supply: Bitcoin's block reward halves every 210,000 blocks. The fourth halving came at block 840,000 on April 20, 2024, and cut the reward from 6.25 to 3.125 BTC. Total supply is capped at 21 million coins, and the last ones are expected to be mined around 2140.
- Access: The U.S. SEC approved the listing and trading of spot bitcoin exchange-traded products on January 10, 2024. The SEC said it "did not approve or endorse bitcoin" and warned that "investors should remain cautious about the myriad risks associated with bitcoin and products whose value is tied to crypto."
- Drawdowns: NYDIG reported that Bitcoin ended 2022 down more than 60%, its second-worst calendar year, after 2018, when it fell more than 70%. A CoinGecko report cited by Fox Business put the 2022 loss at 64%.
Why a "Bitcoin CAGR" does not work for planning
A $1 million projection needs a steady return rate. Bitcoin's average return depends heavily on which start and end dates you pick. Its history covers less than two decades, and in that time it has fallen 60–70% in a single year more than once. If you put an average return into a calculator, the result shows what happens if that average repeats, which it may not. It does not show what is likely.
Two pieces of arithmetic matter more than any projected return:
- Recovery math: After a 50% fall, you need a 100% gain just to get back to where you were. After a 70% fall, you need about 233%.
- Position size: If crypto is 5% of a portfolio and falls 75%, the whole portfolio loses 3.75%. If it is 50% of the portfolio, the same fall costs 37.5%.
Side by side
| S&P 500 index ETF | Bitcoin | |
|---|---|---|
| What you own | Shares in about 500 large U.S. companies | A scarce digital asset with no cash flows |
| Long-run record | ~10% a year, compounded, 1928–2025 | Less than two decades; very uneven |
| Worst recent calendar year | -18.04% (2022) | More than -60% (2022) |
| Past year to October 23, 2026 | Index up about 13% in 2026 | About -25.9% |
| Running cost | 0.03% expense ratio (VOO) | Depends on how it is held |
| What drives returns | Company earnings and dividends | Supply, demand and market sentiment |
What this means for someone starting now
- If you need a plan you can calculate, the index fund is the only one of the two with a long enough record to give you a starting rate. Even then, 7–10% is a more cautious assumption than the last decade's 14.68%.
- Bitcoin is a bet on what happens next, so a fixed savings target cannot rest on it. Position size decides how much its crashes cost you, more than its long-run average does.
- For both, the inputs you can control are how much you put in each month, how long you hold, and costs. The return rate is outside your control.
This is general information, not investment advice. Both assets can lose value, and past returns do not predict future ones.
Limitations: The prices are snapshots from October 21–23, 2026. The compounding figures assume steady returns that real markets do not deliver.
