Millions of older Americans today receive a monthly benefit from Social Security. And many would be unable to cover their basic expenses without that income.
You may be gearing up to collect Social Security yourself at some point, whether in the coming years or in a number of decades. But here are a few reasons why those monthly checks might disappoint you once they start coming in.

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1. You never got an estimate of your monthly benefit
Many people go into retirement assuming that Social Security will pay them roughly what they earned at the tail ends of their careers. Not so.
You should expect Social Security to replace about 40% of the paycheck you used to earn if your salary was average. But you shouldn't expect it to come close to replacing your complete pay.
In fact, this is why it's so important to get an estimate of the monthly Social Security benefit you're in line for ahead of retirement. Doing so is super easy.
Just create an account on SSA.gov and access your earnings statements. If you don't take this step and end up with a benefit you totally weren't expecting (in a bad way), you'll really only have yourself to blame for that lack of information.
2. You didn't plan for benefit cuts
Social Security is facing some financial challenges that could force the program to cut benefits. This isn't expected to happen anytime in the next decade. Rather, based on recent estimates, benefit cuts may be on the table starting in 2034.
But still, if you end up with a smaller paycheck each month from Social Security due to benefit cuts, you're not going to be happy with that. So it's a good idea to brace for benefit cuts and try to work around them.
To be clear, benefit cuts aren't a thing you can control. But you can save in an IRA or 401(k) plan throughout your career (or at least at the tail end if you missed that boat earlier) to help make up for them.
3. You filed at the same time you enrolled in Medicare
Medicare eligibility begins at age 65. You may decide to sign up for Social Security at the same time as Medicare. But that could result in a slashed monthly benefit.
You're not eligible for your complete monthly Social Security benefit based on your personal wage history until full retirement age arrives. That age is 66, 67, or somewhere in between, depending on the year you were born. Knowing the rules when it comes to Social Security and Medicare could prevent you from making the mistake of signing up for benefits at 65 thinking you'll get those monthly paychecks in full.
There's a good chance you'll become reliant on Social Security to a pretty large degree to cover your retirement expenses. So it's important to make savvy moves that lead to a nice monthly payday. It's also important to keep tabs on Social Security and know the rules in the context of filing so you don't end up disappointed with your benefits as a result of your own doing.