Here's What Saving $300 a Month Over 40 Years Could Do for Your Retirement

There's a reason workers are advised to save well for retirement. If you earn an average paycheck, Social Security might replace about 40% of it once you retire -- assuming that benefits aren't subject to cuts.

It's common for retirees to need about 70% to 80% of their former income to live comfortably, which is why Social Security often isn't enough. So if you want to avoid financial struggles, you may need to prioritize retirement savings.

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That doesn't have to mean parting with half your paycheck, though. In fact, you may be surprised at how far a $300 monthly contribution to an IRA or 401(k) might go.

A small amount of monthly savings could yield solid results

If you first start saving for retirement in your 40s or 50s, a $300 monthly IRA or 401(k) contribution may not result in the nest egg you're hoping for. But over 40 years, the math may be on your side.

Let's assume you start saving $300 a month for retirement at age 27. That means you're beginning to fund your nest egg early on in your career, but perhaps not the very moment you start collecting a full-time paycheck.

Let's also assume you invest your money heavily in stocks, and that your portfolio generates a yearly 8% return. That's a bit below the market's average.

If you continue saving that $300 a month through age 67 (which is Social Security's full retirement age) while enjoying an 8% return on your money year after year, you could end up with a balance of about $933,000. That's not a small amount of money by any means. And it could be a nice way to supplement your Social Security checks.

Make sure to give your money time to grow

Clearly, you don't have to part with tons of money every month to build a large nest egg. But if you want to keep contributions smaller, then you'll need to give yourself more time to accumulate wealth.

Let's imagine you only contribute $300 to your savings over a 20-year period. Even with that same 8% return, you're looking at a total of about $165,000 in that scenario.

That's not nothing. But it makes for a very different lifestyle than a $933,000 balance.

Of course, some people struggle to save earlier on in their careers due to heavy student loan debt, high expenses, and lower wages. The point, however, is that if you're able to start funding your nest egg early on, you might get away with contributing a pretty small amount of money each month over time while still building up a sizable balance.

Wait too long, and you may find that you either have to funnel loads of money into your savings each month to make progress, or you end up with a balance that doesn't support the secure retirement you're hoping for.

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