Millions of Americans are working past 65, and it's not because they can't afford to retire

• More retirement-age Americans, mostly baby boomers, are working today than ever before, but it's not because they need the money.
• The largest increase in people working past 65 has been among those in the best shape for retirement: highly educated people with high incomes, says Lincoln Plews, a research analyst at United Income.
• The biggest reason for working longer? They're healthier than they've ever been.
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Not all baby boomers are itching to retire. The greatest share of older Americans in more than 50 years are working well into their 60s, and it's not because they need the money.

That's according to newly released data from the Census Bureau and Bureau of Labor Statistics (BLS) analyzed by investment and financial-planning firm United Income. As of February, about 20% of Americans over age 65 - a total of 10.6 million people - are either working or looking for work, representing a 57-year high.

Today's over-65 population includes baby boomers, defined by Pew Research as ages 55 to 73, and the silent generation, ages 73 and up. The data do not show the specific age breakdown of retirement-age workers.

The full retirement age for Americans born before 1960, which includes millions of baby boomers, is 66 and 10 months; that's the age they're entitled to full Social Security benefits. People can begin claiming a reduced Social Security benefit at age 62, or delay their benefit beyond full retirement age to increase their monthly payout by up to 8% per year, maxing out at age 70.

When should you start taking Social Security? Find out with this calculator from our partners:

The notable increase in retirement-age workers could be explained, in part, by the shift away from workplace pensions and toward defined contribution plans, like 401(k)s, Lincoln Plews, a research analyst at United Income, told Business Insider.

In these types of plans, most of the contributions come from the worker rather than the employer, and Americans are notoriously bad at saving money. It's fair to conclude, then, that some people may need to work longer to make up for a lack of savings come retirement age. And yet, Plews said, the data show scant savings isn't what is driving most old-age workers.

"If you break the data down by education, the largest increase in working past the age of 65 has been seen among those who are in the best shape for retirement, highly educated people with high incomes," Plews told Business Insider. "According to the Federal Reserve's 2016 Survey of Consumer Finances, people with a college degree still working past age 65 have a median net worth of $706,000. For those in this group with an above-average income, the median is just over $1.4 million."

Plews found that the share of over-65 workers with at least a college degree increased from 25% in 1985 to 53% in 2019, bumping up the average income for retirement-age workers from $48,000 to $78,000, after adjusting for inflation.

Further, the numbers show there's another, more intangible, factor at play: longevity.

"Retirement-age Americans are feeling healthier than ever. More than three out of four Americans aged 65 or older report being in good, very good, or excellent health, and this proportion has grown steadily over the past 35 years," Plews wrote in the United Income report.

Improved health means Americans are feeling more capable than ever, the report found. Seventy-seven percent of over-65 workers said there are no limitations in the kind of work they can do.

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