How much young people are really earning doing side hustles

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More than half of U.S. millennials are running side hustles, picking up extra cash outside of their regular day jobs doing everything from babysitting to reselling stuff online — and some are making a pretty penny doing it, according to according to a new study by Bankrate.

Fifty-one percent of millennials have at least occasional side hustles that they rely on for a cash stream outside their primary source of income, finds Bankrate. The personal finance site surveyed a little over 1,000 people across various age groups and income brackets and found that roughly 37 percent of Americans overall engage in a regular side hustle, including 28 percent who perform their side hustle at least once a month, if not more often.

But regular side hustles are especially popular among American millennials — 38 percent of people ages 18 and 37 told Bankrate that they make money from their side hustles at least once a month. That's compared to 30 percent of Gen Xers (ages 38 to 53) and 24 percent of Baby Boomers (ages 54 to 72). Bankrate also found that 15 percent of millennials earn money from their side hustle a weekly basis, 10 percent "a few times" each month and 13 percent once a month.

The most popular side hustles for millennials are "home repair/landscaping" (12 percent), according to Bankrate. A total of 9 percent of millennial respondents make additional money babysitting and 8 percent selling or reselling goods online, including via sites like Ebay, according to the survey. Other millennial side gigs include substitute teaching or tutoring; doing hair or makeup; earning money by finishing online surveys or completing tasks for people online; or doing freelance photography and videography (4 percent each).

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How much are they earning via side hustles? The average monthly earnings for millennials with side hustles is almost $580 (compared to $686 per month across all age groups), Bankrate found.

Broken down, 15 percent of millennials earn over $1,000 per month; 20 percent earn between $201 and $1,000 a month; 21 percent pull in $101 to $200 a month; 15 percent make between $51 to $100 per month; and the largest number of millennial respondents (22 percent) said they typically earn $50 or less each month.

What's more, the vast majority of millennials (68 percent) with side hustles describe their additional cash flow as merely "disposable income" that they spend on things aside from their regular living expenses. But 32 percent of the millennial respondents say they rely on their side gigs to cover necessary living costs like housing and food.

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