Start Investing at 25 Instead of 35: The Math Shows You’ll Have $426,000 More by 65

A 25 year old who invests $5,000 a year for a decade and then never contributes another dollar ends up with $426,000 more at age 65 than someone who waits until 35 and does the exact same thing. Same money in. Same return assumption. Same stopping point. The only difference is the starting line.

That’s the math George Kamel walked through in his video There’s Something Really Messed Up About This Finance Quiz, and it’s the cleanest argument against waiting to invest I’ve come across. I’ve been writing about personal finance for years now, and this is the one example I keep pulling out when someone in their twenties tells me they’ll start “once they make more.”

The verdict: Kamel is right, and the gap is bigger than most people think

Investor A puts $5,000 a year into the market from age 25 to 34. Ten contributions. Then stops forever. Investor B waits, then puts $5,000 a year in from age 35 to 44. Also ten contributions. Both people put in $50,000 of their own money over ten years, and both assume an 8% annual return.

At the end of each person’s ten year contribution window, the balances are identical: $65,594. If you froze the clock there, you’d think these two paths were equal. The next thirty years tell a different story.

Fast forward to age 65 and Investor A has $776,856. Investor B has $349,991. The earlier starter’s pile keeps doubling in the background while the later starter is still trying to catch up to a moving target.

Kamel’s takeaway: “The lesson here is actually incredible, is the power of compound growth takes time, and the more time you have, the results are exponential.”

Why 8% isn’t a fantasy number

The first pushback I hear is that 8% sounds optimistic, but the history backs it up. The S&P 500, tracked by SPY, has returned 261% over the last ten years and 445% since November 1999, a stretch that includes the dot com crash, the 2008 financial crisis, and the 2020 pandemic shock. Long run equity returns in the 8% to 10% range are the historical baseline.

Compare that to the alternative most cash savers default to. The 10 year Treasury is yielding about 4.4%. Safe, but in a world where CPI sits at 332.4 and recent monthly inflation came in at 0.6%, half of that yield gets eaten by rising prices. Treasury yields preserve purchasing power. Equities grow it.

The variable that decides everything: when you start, not how much

The variable that matters is start date, not income.

If Investor B wanted to catch Investor A by age 65, contributing only from 35 to 44, she’d need to put in roughly $11,000 a year, more than double, just to land in the same place. The American personal savings rate was 4% in the first quarter of 2026, down from 5.2% a year earlier. On a per capita disposable income of $68,617, that’s not a lot of room to suddenly double anything.

The variable cuts the other way too. If you’re 25 and reading this thinking $5,000 a year is impossible, $2,000 a year still beats $10,000 a year started at 40. Time is doing the heavy lifting. Your contribution size is the lever you adjust later.

The actual sequence to run

Kamel’s prescription is direct: “Get a head start and get out of debt, get that emergency fund, get investing as soon as possible. Don’t say, ‘Well, it’s a problem for future me. I won’t worry about that.'”

Here’s how I’d operationalize it:

1. Kill high interest debt first. Anything above 8% is mathematically beating the market return you’re chasing. Credit card balances at 22% are a guaranteed negative return. Pay them down before you fund a brokerage account.
2. Stash a one month emergency buffer, then start investing in parallel. A smaller starter buffer plus a Roth IRA contribution beats waiting two years to build a perfect cushion.
3. Automate $100 a week into a low cost S&P 500 index fund. That’s roughly $5,200 a year. Set the transfer the day after payday so you never see the money.
4. Capture every dollar of employer 401(k) match. That’s an instant 50% or 100% return depending on the match formula, and it stacks on top of the compounding math above.
5. Increase the contribution by 1% of salary every year. You won’t feel it. Your future balance will.

Kamel closes with a line worth taping to your monitor: “There’s no reason to retire broke in America today.” The $426,000 gap is a reward for starting early. The 25 year old who automates $100 a week and forgets about it walks past the 35 year old who waited for the perfect salary. Every time.