Americans are living longer these days. That's a positive thing in theory, but from a retirement-planning standpoint, it can be challenging. After all, there's a difference between needing your retirement savings to last 20 years versus 30 years or more.

Of course, without a crystal ball, it's impossible to predict how long your retirement will last. But if you want to help ensure that you don't run out of money down the line, then it pays to take these steps to safeguard yourself in the event you live longer than anticipated.

Older man and woman walking and holding hands


1. Boost your nest egg

The more savings you have going into retirement, the easier it'll be to stretch that money out over a lengthier period of time. If you're not in the habit of maxing out your IRA or 401(k), aim to get as close to the annual limits as possible. And if you can't do that, try saving more than you're currently saving.

Imagine, for example, that you contribute $300 a month to your IRA over a 40-year period. If your investments in that account generate an average annual 7% return (a reasonable assumption when stocks comprise the bulk of your portfolio), you'll end up with about $719,000. Now that's a decent chunk of savings by itself. But if you're able to save $400 a month over those 40 years instead, you'll end up with roughly $958,000, assuming that same return. And having that extra $239,000 could come in handy if you wind up living 10 years longer than the typical retiree.

2. Delay your Social Security benefits

You're entitled to collect your full monthly Social Security benefit based on your earnings history at what's known as full retirement age. That age is either 66, 67, or somewhere in between, depending on your year of birth. However, you're also allowed to delay benefits past full retirement age, and for each year you do, you'll increase those payments by 8%.

Now this incentive does run out at age 70, so if your full retirement age is 67, the most you can do is increase your benefits by 24%. But that's quite the sizable boost, and it's a good way to guarantee yourself more retirement income for life.

3. Come up with a plan to downsize your lifestyle

If you're only able to save so much for retirement, and you know your Social Security benefits will only cover a portion of your total senior living expenses, then you may need to devise a plan to spend less money in general. That way, you'll lower your risk of depleting your nest egg prematurely.

Take a look at your current lifestyle and think about ways you can downgrade it from a financial standpoint. You could consider moving to a less expensive part of the country -- one where a lower cost-of-living will help you maximize your savings and Social Security income. Or, you could stay put but move to a smaller home, and plan to entertain yourself locally rather than travel the globe. There are different options you can play around with, but the key is to do some thinking and come up with a solution that allows you to spend less money but still be reasonably happy.

4. Secure multiple income streams

Living longer means withdrawing more conservatively from your IRA or 401(k). To compensate for giving yourself a lower monthly paycheck from savings, try lining up other income streams. You could get yourself a part-time job -- one you do independently, or one that requires you to report to a physical location on a preset schedule. You could also try renting out a portion of your home and collecting monthly income from a tenant.

You might think your retirement will only last 15 or 20 years, but Americans are living longer these days. About one in every three 65-year-olds today will live past age 90, while around one in seven will live past 95. Rather than bemoan the idea of good health and longevity, plan for the fact that you might live longer so that your senior years are stress-free and financially sound.