Senior Balloon Jeffrey Smith

Source: Flickr user Jeffrey Smith

The Social Security Administration estimates that the average 70-year old woman will live to nearly 88 years old. Unfortunately, those next 18 years are likely to include a lot of unexpected spending on medical care. Will the money you worked so hard to save still be there when you most need it? Read on to find out what strategies our Motley Fool contributors think could help make sure that it is.

Todd Campbell: Be realistic about how long you might live. Too often retirees determine how much they will withdraw from retirement accounts based on their wants, rather than their needs, and that can mean that savings are drawn down too quickly.

Instead of heading into retirement thinking, "I need 80% of my pre-retirement income in retirement," run the numbers and then look for expenses to cut. In doing so, you may discover that you're fine with 50% of your pre-retirement income. If so, then combining Social Security with part-time employment may be able to do a lot of the heavy lifting.

Remember, planning ahead and thinking long-term doesn't stop when you hit 65. Your retirement savings probably won't grow by more than an average 4% to 6% in retirement, so withdrawing more than that could result in running out of money too soon. For that reason, embracing the same money-wise strategies that got you to retirement may still be the best approach in your golden years.

Selena Maranjian: It's hard to be sure that your money will last for your whole life, because who knows -- you may live to the age of 110, requiring your nest egg to stretch over 45 years. (Hey, it could happen.) One way to get almost-guaranteed income for the rest of your life is via an immediate (or deferred) fixed annuity. (A fixed annuity offers payments that are spelled out in advance and not tied to the performance of stock market indexes or other things, as with variable annuities or indexed annuities, which can be more problematic investments.)

Immediate or deferred fixed annuities are smart options for many retirees or those approaching retirement. You pay an insurance company a lump sum (or installments) and in return you receive payments -- now or later. The payments are often monthly, but can be quarterly, annually, or even a lump sum. They can last for a fixed number of years or for the rest of your life. Pay a little extra (or accept smaller checks) and you can have your payouts last until your spouse's life, too, and/or be adjusted to keep up with inflation over the years.

As an example, if you're a 70-year-old man, $100,000 may get you an immediate annuity paying about $640 per month, or $7,700 per year. A $300,000 purchase would generate about $23,000 annually. That's a meaningful sum, more than what the average retiree receives from Social Security each year (about $16,000). If the 70-year-old spends $100,000 on a deferred annuity that begins paying in five years, he can collect roughly $1,000 per month.

Learn more about fixed annuities and see if one or more make sense for you.

Dan Caplinger: One thing that many people approaching retirement get wrong is that they sell off all of their stock market exposure. Financial planners agree that reducing your exposure to stocks somewhat in retirement makes sense, but getting rid of stocks entirely can be a big mistake.

The problem that those in or approaching retirement face is that even though they're not bringing in any income from a job, they still face the prospect of having to make sure their money will last a long time. Many retirees live 30 years beyond when they quit their jobs, and so you have to make sure not only that you'll be able to preserve your portfolio over time but also make it grow at least initially to make sure you can provide for your needs in the distant future.

With bonds and other fixed-income investments earning next to nothing right now, the best way to ensure that you can get the long-term growth you need is to keep a respectable portion of your portfolio in stocks. The volatility of the stock market might force you to make spending adjustments from time to time, but the long-term likelihood of outliving your money rises dramatically if you can stomach the ups and downs to get the better returns that stocks have provided historically.

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