For many retirees, Social Security benefits make the difference between enjoying a comfortable retirement and struggling to make ends meet. Roughly 20% of married couples and close to half of unmarried beneficiaries rely on their monthly checks for at least 90% of their income, according to the Social Security Administration (SSA), so that money can be incredibly important in retirement.

Because your benefits could make up a significant portion of your income in retirement, it's crucial to ensure you're doing everything you can to maximize them. And there's one easy move you can make right now that will help set you up for retirement success.

Social Security card

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A little preparation goes a long way

When it comes to retirement, the more you prepare, the better off you'll be. The same is true for Social Security, and when you know what to expect in terms of benefits, the better you'll be able to prepare financially.

One of the easiest things you can do to get ready for retirement is to check your Social Security statements online to see how much you're expected to receive in benefits. It only takes a few minutes to create a my Social Security account and check your estimated future benefit, yet less than half of Americans who have an account have logged in to see their statements, according to the SSA.

Checking your future benefit is helpful for a couple of reasons. First, it gives you a realistic sense of how much you can rely on your benefits in retirement. If you're expecting Social Security to cover all your living expenses, seeing your statements can be a reality check if you won't be receiving as much as you think. And second, it can help you plan how much you need to save on your own to make sure you'll have enough income in retirement.

Say, for instance, you estimate you'll need around $50,000 per year to cover your expenses in retirement. If you check your Social Security statements and learn you'll be receiving $20,000 per year in benefits, that means that only $30,000 per year will need to come from your savings (assuming you don't have any other sources of income in retirement). The earlier you have this information, the easier it will be to plan for retirement. If you simply wing it and hope that your savings and benefits are enough to cover all your costs, you may need to make some big sacrifices in retirement if that money isn't enough.

How the age at which you claim affects your benefits

When you check your benefits online, it's important to keep in mind that the actual amount you'll receive depends on the age you begin claiming. To receive the full benefit amount you're entitled to, you'll need to wait to claim until your full retirement age (FRA) -- which for those considering benefits now is either 66, 66 and a few months, or 67, depending on the year you were born. If you claim before your FRA, your checks will be reduced by up to 30%. On the other hand, if you wait until after your FRA to claim, you'll receive a little extra money each month on top of your full benefit amount.

If you're expecting to rely on your benefits for a good portion of your retirement income, it's extra important to make sure you're claiming at the best age for you. Sometimes it might be smart to delay benefits and earn those bigger checks if you have little to nothing saved. Or if you have a healthy retirement fund and can survive on smaller checks, claiming early may be the way to go. Regardless of your decision, make sure you've thought about how the age at which you claim will affect the size of your monthly checks.

Social Security benefits may be a significant part of your retirement, so it's a good idea to make sure you understand what you're expected to receive when you begin claiming. Checking your online statements only takes a few minutes, but it can help you create a much more thorough retirement plan.