Social Security benefits are a crucial factor in many Americans' retirement plans, so it's wise to make sure you understand the program as much as possible. While you don't necessarily need to know all the nitty-gritty details behind how your benefits are calculated, it's a good idea to at least understand the basics.

However, many older workers who are nearing retirement age are in the dark about their benefits. In a MassMutual survey of Americans age 55 to 65 who had not yet claimed benefits, only 3% of survey participants could correctly answer 12 true-false questions about Social Security. And there's one question in particular that tripped up nearly half of near-retirees.

Social Security card

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The aspect of Social Security many workers struggle with

The age you begin claiming benefits will affect how much you receive each month for the rest of your life, so it's a decision that shouldn't be taken lightly. If you claim at your full retirement age (FRA) -- which is age 67 for those born in 1960 or later, or either 66 or 66 and a few months for those born before 1960 -- you'll receive the full benefit amount you're theoretically entitled to. But if you claim before or after that age, you'll receive smaller or bigger checks.

A whopping 94% of survey respondents answered correctly when asked whether claiming earlier than their FRA would reduce their monthly benefit amount. However, only 53% of respondents gave the correct answer when asked if delaying benefits beyond age 70 would result in bigger checks.

While delaying benefits past your FRA will result in a bigger check each month, these benefit bonuses stop at age 70. So although you can wait until after age 70 to file for Social Security, you won't receive any additional money each month by doing so. In other words, there's no real reason to wait until after age 70 to start collecting benefits.

This misconception can be dangerous, however, because if you're planning on waiting until after age 70 to collect benefits thinking you're going to get more money for each year you wait, you may be in for a rude awakening when your benefit amount doesn't increase. If you're banking on that extra cash to fund your retirement, not getting that benefit boost you were counting on could throw off your retirement plans.

How to choose the right age to claim benefits

Determining when to claim benefits isn't always easy, but it's important to take this decision seriously. To figure out which age is best for you to claim, there are a few factors to consider.

First, think about your life expectancy. In theory, you should receive approximately the same amount in benefits over a lifetime no matter when you begin claiming. If you claim early, you'll receive smaller checks but more of them. Delay benefits and you'll receive fewer checks, but they'll each be bigger. However, these calculations assume you'll live an average lifespan (or around 85 years, according to the Social Security Administration).

If you think you may live a longer- or shorter-than-average lifespan, you may consider delaying benefits or claiming early. After all, if you have reason to believe you may only live into your mid-70s, waiting until age 70 to claim doesn't give you much time to enjoy your benefits. But if you're in the best shape of your life and everyone in your family has lived to be 100 years old, delaying benefits might mean collecting more money over a lifetime.

A second factor to consider is how badly you need the money. If you have a healthy retirement fund and don't necessarily need the extra cash from Social Security, claiming early can provide you with a little extra spending money earlier in retirement. But if your savings are slim, delaying benefits and earning those bigger checks can make for a more comfortable retirement.

For many older Americans, Social Security benefits can make or break retirement. And if you don't fully understand how the program works, it can be tough to make smart decisions to maximize your monthly checks. The more you know about Social Security, however, the better off you'll be in retirement.