Millions of seniors rely on Social Security to pay the bills in retirement. Regardless of whether you think those benefits will comprise a small portion of your retirement income or the majority, they'll no doubt play a role in shaping your financial picture as a senior. With that in mind, here are a few steps you can take to avoid losing out on Social Security income when you need it the most.

1. Wait until full retirement age to file for benefits

Though your Social Security benefits are calculated based on how much you earned during your working years, the age at which you first file for them can cause that number to shift. If you wait until full retirement age to claim benefits, you'll get the full amount your work history entitles you to. But if you sign up for Social Security at any point ahead of full retirement age, you'll face a reduction in benefits that will remain in effect for the rest of your life unless you're able to undo your application within a year of filing and pay back the money you received.

Senior man looking at a wall calendar

IMAGE SOURCE: GETTY IMAGES.

For today's workers, full retirement age is either 66, 67, or 66 and a certain number of months. Be sure to understand when you're eligible to get your benefits in full to avoid losing out on money in your lifetime.

2. Make sure your earnings record is correct

Your salary history will dictate how much money you're entitled to from Social Security at full retirement age. But if the Social Security Administration (SSA) has that information wrong, you could lose out on money that should've otherwise been yours. That's why it's crucial to log onto the SSA's website at least once a year, access your earnings history, and review it for accuracy. If you come to spot an error that works against you -- say, your income for a given year is listed as lower than what you actually earned -- you'll want to report it to the SSA right away to get it corrected.

Keep in mind that unless you're 60 or older, you won't get copies of your earnings statements in the mail. Rather, you'll need to proactively log onto the SSA website and get at that information yourself.

3. Put in at least 35 years in the workforce

Your 35 highest years of earnings are taken into account when determining your full monthly Social Security benefit amount. Therefore, if you didn't work for 35 years, you'll get a $0 factored in for each year that's missing an income. Now if you're no longer able to work (say, your health won't allow for it or you got laid off and have struggled to become reemployed), there's really not much you can do to fill in those earnings gaps. But if you have the option to extend your career, doing so could boost your benefits by virtue of replacing some $0s with actual earnings figures.

Imagine that you only worked for 33 full years, and that you're planning to retire at 65. If you work until 67 instead at an $80,000 a year salary, that income will be factored into your benefits calculation to bring up your total number. Incidentally, in this example, extending your career will also help you avoid filing for benefits early and reducing them in the process.

4. Fight for raises throughout your career

The more money you make on the job, you more you stand to collect from Social Security. So if you make a point of continuously fighting for higher pay, you might boost your benefits substantially as a result.

Of course, negotiating raises is easier said than done, so the best way to be successful in this arena is to go in prepared. Start by doing your research to see what other people with your job title are bringing home. If you find that you're being underpaid at any stage of your career, that's a compelling argument to present to your boss. Additionally, keep a running list of the ways you've gone above and beyond at work, or have contributed meaningfully to your company's success, and review it with your manager as needed. The more you're able to prove your value, the greater your chances of getting the salary boosts you're after.

The more money you get out of Social Security, the less financial stress you'll experience during retirement. Follow these tips, and with any luck, those monthly payments you eventually come to collect will be as robust as possible.

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