Today’s young people fear that they will never see Social Security benefits. The reality is, 3% of elderly Americans already don’t.

The three main groups of people who never receive Social Security benefits include infrequent workers (44.3%) who do not have sufficient earnings to qualify for the benefits, immigrants who arrived in the U.S. at 50 or older (37.3%) and therefore haven’t worked long enough to qualify for the benefits, and non-covered workers (11.4%), such as state and local government employees. A little less than 7% of “never beneficiaries” were individuals who were expected to get Social Security benefits, but died before receiving them, according to a 2015 Social Security Administration report.

What’s worse, most Americans may not realize how much they will — or will not — receive in Social Security benefits, said Bill Meyer, chief executive of Social Security Solutions, a software provider that strategizes how to claim Social Security. Social Security benefits are based on earnings history from the past 35 years — “The onus is on the individual retiree that the Social Security Administration has the right information,” Meyer said.

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Social Security benefits are hotly contested, specifically how — or even whether — those benefits will be distributed in the future. Young Americans say they’re not confident they’ll ever collect Social Security benefits (81% of millennials didn’t think so, at least, according to a recent Investopedia survey) but current near retirees may also be at risk. In December, the House Ways and Means Social Security Subcommittee introduced a bill that would “save” Social Security by cutting benefits for above-average earners, eliminating the cost-of-living adjustment for individuals who make more than $85,000 (and $170,000 for couples), and increasing the full retirement age to 69 from 66.

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There were about 58 million beneficiaries receiving Social Security payments in February, according to the SSA, and the average monthly benefit was $1,249.55.

Using tools to determine how much you will receive in Social Security benefits, or analyze the best strategies for claiming, can help with planning for the future, said Andrew Way, senior analyst of retirement at research firm Corporate Insight. There are free and paid programs, which all provided similar results but explained the benefits in different contexts, according to a Corporate Insight study. “Knowledge is key,” he said. “You need to know what your situation is and what you can perhaps receive.” (One way to find out about your Social Security benefits is by signing up for a “My Social Security Account.”)

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Benefits are also affected by how long you live, which is changing dramatically — people are living longer now than they did decades ago. People born in 1900 often did not live past 50 years old, but today life expectancy is into the 80s across the world, according to the National Institute on Aging, and about one of every four 65-year-olds will live past 90, according to the SSA. It’s important to factor in life expectancy based on your current age and condition as opposed to your birth year, though, financial services company Motley Fool wrote, since life expectancy at birth could be less than how long you may actually live.

Once near retirees have a copy of their Social Security earning history, they should consider which claiming strategy is best for them, Meyer said. He recommends that unless you expect a short life expectancy or financial circumstances require funds more quickly, you should wait to claim your benefits until you’re 70, since the cumulative benefits will be worthwhile. Also, it’s important to be your own advocate, and know where you can get the most money — for example, men and women can claim their spouse’s or ex-spouses’ benefits without affecting them, which can also affect what you get in Medicare, said Philip Moeller, author of “Get What’s Yours for Medicare” and co-author of “Get What’s Yours: The Secrets to Maxing Out Your Social Security.”

“The Social Security Administration does not give you advice,” Meyer said. “They’ll only give you information about your own situation.”