You want to save for retirement, but finding the cash is tough. Even with a budget that minimizes discretionary spending, you still have bills to pay and more immediate financial goals to save for. All you can afford to spare is $100 per month.

That might not seem like much, but it could go surprisingly far, depending on how you invest it. But whether it’s enough to retire comfortably depends a lot on your lifestyle.

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The longer you invest your money and the greater your investment return, the more you’ll wind up with by retirement. Let’s say you start saving $100 per month at 25 and plan to retire at 65. If you earn a 10% average annual return during that time, you’d have about $555,000 by retirement, despite only contributing $48,000 of your own money.

But if you got a late start or your investments don’t perform as well, you could wind up with less than this. That could be a problem, particularly if you live in an expensive city or you’re in poor health.

On the other hand, you likely won’t have to cover your retirement expenses entirely on your own. If you qualify for the $2,083 average monthly Social Security benefit as of May 2026, you’d get roughly $25,000 per year in benefits. Over 20 years, that’s roughly $500,000, not counting cost-of-living adjustments (COLAs).

Again, whether that’s enough for you to retire on depends on your lifestyle. But the above example shows that saving $100 per month can really add up over time. Start there if that’s all you can afford right now. Then, if you get a raise or a new job, increase your retirement contributions before you do anything else.

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