Working one job isn't always enough. Gen Zers and millennials are taking on side hustles and freelance work.

A new study finds 80% of Gen Zers have worked outside their main jobs.

LeoPatrizi/Getty Images Goldman Sachs Asset Management found 80% of Gen Zers have worked outside their primary jobs.

People across generations said this was because they needed the money or for financial security.

Not feeling secure can affect financial goals, like homeownership.

Having a job doesn't always mean you have enough to cover daily living or savings goals.

A July survey of Americans by Goldman Sachs Asset Management and the behavioral economics firm Escalent found over 60% of respondents have worked outside their primary roles, largely because they needed to.

Twenty-seven percent of respondents said work covers their expenses, but it's tough to get ahead.

"Employment remains essential for retirement security, but for many Americans, it is no longer sufficient," a Goldman Sachs Asset Management retirement report said.

Gen Zers were most likely to say they earn or have earned money outside their primary job; millennials followed closely behind.

The report said that's despite most Gen Z and millennial workers reporting their jobs provide financial stability.

"Younger workers may feel stable in their main jobs while still seeing extra work as necessary," the report said.

Throughout the generations, a majority said they're doing gig or side work out of necessity or for financial security.

"The traditional full-time job may no longer be carrying the full weight of financial security," the report said.

"For many, supplementing income appears to have become part of the baseline." Some Americans are living paycheck to paycheck or adjusting their budgets to cope with rising gas prices and other everyday expenses.