Social Security is a guaranteed source of income in retirement, and it can ease the burden on your personal retirement savings, helping you stretch your dollars further. But the amount you receive depends on several factors, including when you begin claiming benefits and how much you earned during your years in the workforce. It's important to understand how these pieces all fit together or you could make a mistake that costs you tens of thousands of dollars in Social Security benefits over your lifetime. Here are three big Social Security faux pas you don't want to make.

1. Working less than 35 years

Your Social Security benefit is based on your average monthly income during your 35 highest-earning years, with adjustments for inflation. If you haven't worked for at least 35 years, the Social Security Administration (SSA) will add zeros to your calculations, and this will reduce how much you're entitled to. If you've worked less than 10 years, you might not be eligible for Social Security retirement benefits at all.

It's worth noting that these years don't have to be consecutive. The SSA uses a credit-based system to determine Social Security eligibility. In 2019, you earn one credit for every $1,360 you make, with a maximum of four credits per year. You need 40 credits (10 years) to be eligible for Social Security.

2. Not checking your earnings record

Everyone should create a My Social Security account with the SSA. This will give you an idea of how much to expect from Social Security if you start taking it at different ages, and you can also view a copy of your earnings record. It's important that you check this information every year to be sure it's accurate because this is what your benefit is based on.

If the SSA has the wrong information, it could underestimate your average monthly earnings, which means you'll get a smaller check than you deserve. There isn't anything you can do about it either, unless you have the tax documents to prove how much you actually earned. This is why you shouldn't throw out any of your tax paperwork unless you're confident that the government has your correct earnings for that year recorded. If you find an error, fill out a Request for Correction of Earnings Record and submit this to the SSA, and then check your Social Security account to make sure the record is updated.

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