Millions of retirees depend on Social Security to pay the bills, so much so that 62% of seniors count on it to provide half of their income or more. Unfortunately, nearly half of the U.S. adult population is missing key knowledge needed to make the most of those benefits.

In recent quiz rolled out by Mass Mutual, a frightening 47% of Americans could not answer basic questions about full retirement age and spousal benefits -- two key components of Social Security. Specifically, respondents didn't know that their benefits would be reduced if they were to file at age 65, nor did they know that spouses of eligible recipients can collect benefits even without a work history of their own.

Person holding Social Security card

Image source: Getty Images.

If you're planning to have Social Security pick up a large chunk of your retirement tab, you'd be wise to get the scoop on the aforementioned topics. This way, you can devise a filing strategy that best serves your needs in the future.

Full retirement age: It pays to wait to claim benefits

Your Social Security benefits themselves are calculated based on how much you earned during your top 35 working years, but the age at which you first file for them could change your ultimate monthly payout. If you claim benefits at full retirement age (FRA), you'll get the full monthly benefit your earnings record entitles you to. FRA is a function of your year of birth, as follows:

Year of Birth

Full Retirement Age

1943-1954

66

1955

66 and 2 months

1956

66 and 4 months

1957

66 and 6 months

1958

66 and 8 months

1959

66 and 10 months

1960

67

Data source: Social Security Administration.

That said, you can actually start taking benefits as early as 62, which happens to be the most popular age for filing. In doing so, however, you'll slash your benefits significantly, so if you're relying on Social Security to provide a large portion of your retirement income, you may want to hold off until FRA or even beyond. In fact, for each year you delay benefits past FRA, you'll snag an 8% boost that will remain in effect for the rest of your life. This incentive, however, runs out at age 70, which is why 70 is generally considered the latest age to file for benefits, even though you're technically not forced to sign up at that time.

Furthermore, many people assume that they're eligible for their full monthly benefits at age 65 because that's when Medicare kicks in. But that's not true. You can enroll in Medicare and get health coverage the moment you turn 65, but if you sign up for Social Security simultaneously, you'll lose a portion of your benefits by enrolling early.

To give you a sense of how much you'd lose by filing ahead of schedule, imagine you're looking at an FRA of 67 and a full monthly benefit of $1,500. Filing at 62 will reduce each payment to $1,050. Waiting until 70, by contrast, will leave you with $1,860 a month in Social Security income.

Spousal benefits: You don't need to work to collect Social Security

We just learned that Social Security benefits are earnings-based, but if you're married without a work history of your own, you're in luck. That's because you're eligible to collect up to 50% of your spouse's benefit at your full retirement age. Going back to the point above, if your spouse files for benefits ahead of FRA and reduces them, you'll also collect less. Similarly, if you, as the recipient of spousal benefits, decide to file early, you'll lose a percentage of the monthly payment you'd otherwise be entitled to.

Another thing you should know about spousal benefits is that you can collect them even if you have a work record of your own. If your monthly benefit based on your earnings history is $800 and your spouse is entitled to $1,800 per month, your benefit will automatically get bumped up to $900, or 50% of your spouse's benefit. Finally, whereas holding off past FRA can boost your personal benefit, you can't increase your spousal benefit by waiting.

Understanding the nuances of Social Security can help you maximize your benefits when it's time to collect them, so do your best to get educated about the program while you're still working. A little bit of basic knowledge could help you make the best filing decision, and that's something you'll no doubt appreciate as a retiree.

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