As parents know all too well, just because your children have moved out, it doesn't mean you're off the hook.
Whether it's $100 a month for food or $500 toward a student loan bill, nearly 40% of empty nesters are still financially supporting their children in some way, according to a new report by 55places, an adult community comparison site.
To that end, the average parent shells out $254 each month, the report found.
"There's always been this notion that, once your children start their career, you are home free, and many empty nesters have found that that's not the case," said Bill Ness, the CEO and founder of 55places.
"Enough empty nesters realize that there are a lot of expenses that their children will incur and it will be very difficult if not impossible."
In fact, millennials face financial challenges that their parents did not as young adults. On top of carrying most of the $1.5 trillion in student loan debt, their wages are lower than their parents' earnings when they were in their 20s.
A 2017 study of Federal Reserve data by advocacy group Young Invincibles showed that millennials earned an average of $40,581 in 2013. That's 20% less than the inflation-adjusted $50,910 earned by baby boomers in 1989.
In addition, rents continue to rise even as housing prices outpace wages, making it even harder for those just starting out to go it alone.
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As a result, nearly a quarter, or 24%, of empty nesters are covering cell phone expenses, while 19% of parents help with rent and another 18% foot the bill for groceries, 55places found. About 15% help cover their child's student loan repayments after graduation.
More millennials are also living with their parents longer. The average age parents expected their children to move out was 21, but nearly half said their child was 21 or older by the time they actually left the nest, 55places found. The site surveyed more than 1,800 empty nesters between June and July.
A separate report by Merrill Lynch and Age Wave found that 58% of early adults, which Merrill defines as those between the ages 18 and 34, said they would not be able to afford their current lifestyles without parental support.
And yet financial experts warn that supporting grown children can be a significant financial burden when retirement looms.