Social Security can be a confusing topic, but considering 88% of workers expect to depend on their benefits at least somewhat in retirement, according to a survey from Gallup, it's important to understand as much as possible to maximize your monthly checks.

There's one misconception in particular that the majority of near-retirees share. And if you fall for it, it could potentially cost you hundreds of dollars per month.

Older man sitting behind a laptop looking worried

Image source: Getty Images.

The costly mistake you may not realize you're making

One of the most important factors to understand when it comes to Social Security is your full retirement age (FRA). If you were born in 1960 or later, your FRA is 67. For those born before 1960, your FRA is either 66 or 66 and a certain number of months, depending on the exact year you were born.

By claiming at your FRA, you'll receive the full benefit amount you're entitled to collect. You can claim earlier than your FRA, but you'll receive smaller checks each month.

A common misconception is that if you claim early, your benefits will only be reduced until you reach your FRA, at which point you'll start receiving your full benefit amount. In fact, nearly 70% of baby boomers share this belief, a survey from Nationwide found. However, the truth is that when you claim before your FRA, you'll receive lower monthly payments for the rest of your life. If you're expecting your benefit amount to increase once you reach your FRA, you could be in for an expensive surprise.

How this misconception could affect your retirement

If you're claiming early under the assumption that your monthly payments will increase at your FRA, you may not collect nearly as much each month as you expect.

The average retiree collects $1,514 per month in benefits, according to the Social Security Administration. Say you have an FRA of 67 years old, and you'd receive $1,514 per month by claiming at that age. By claiming early at age 62, your benefits would be reduced by 30%, leaving you with $1,060 per month.

In other words, you may be anticipating a $450 per month boost in benefits once you turn 67 years old, but in reality, you'll be stuck with those smaller checks for life. That could have a major impact on your retirement, especially if you're going to be relying on Social Security for a substantial portion of your income.

Ways to boost your benefit amount

If Social Security benefits are going to be a significant source of income for you in retirement, it's a good idea to ensure you're doing everything you can to collect as much as possible each month.

One way to increase the size of your monthly checks is to delay claiming benefits. By waiting until after your FRA to file for Social Security, you'll receive your full benefit amount plus a bonus of up to 32% every month. Because your benefit amount is generally locked in for life once you begin claiming, when you delay benefits, you'll receive larger checks every month for the rest of your retirement.

Other options to boost your benefits include working longer or increasing your income. The Social Security Administration calculates your basic benefit amount (or the amount you'll receive by claiming at your FRA) by taking an average of your income over the 35 highest-earning years of your career, then adjusting it for inflation. By working for more than 35 years or boosting your income, you can increase your earnings average as well as your benefit amount.

You don't need to know all the nitty-gritty details about how your benefits are calculated, but by understanding the basics, you can take steps to increase the size of your monthly checks. Social Security benefits are a lifeline for millions of retirees, so the more you're receiving each month, the better chance you have of enjoying a comfortable retirement.