Most people feel like a grownup by the time they're 18, but these days young adults might not become financially independent until years later.
And even then, parents and their children could disagree on what exactly that means.
While young adults said 21 is a good age to start paying some of their own expenses, older generations are more likely to think that their kids should be completely financially independent by then, according to a new report by Bankrate.com.
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In part, millennials and Gen Z face financial challenges that their parents did not as young adults. On top of carrying much more student loan debt, their wages are lower than their parents' earnings when they were in their 20s and 30s.
Of course, inflation has made it even harder for those trying to achieve financial independence. Soaring food and housing costs pose additional hurdles for young adults just starting out.
Now, 68% of parents with children over age 18 are making a financial sacrifice to help support them, according to Bankrate's report.
From buying groceries to paying for cell phone plans or covering health and auto insurance, parents are spending more than $1,400 a month, on average, helping their adult children make ends meet, a separate report by Savings.com found.
When 'offering financial assistance can backfire'
For parents, however, supporting grown children can be a substantial drain at a time when their own financial security is in jeopardy.Â
"Remember that saying about putting your oxygen mask on before helping others?" said Ted Rossman, Bankrate's senior industry analyst. "Offering financial assistance can backfire if it puts your own savings, investments and financial well-being at risk."
About half of parents with adult children said that support has come at the expense of their own emergency savings or ability to pay down debt, while slightly fewer said supporting their children has been detrimental to their retirement savings, Bankrate found.
'Where to draw the line'
"It's hard to know exactly where to draw that line," Rossman said. Make sure the assistance works within your budget and be clear about the parameters — at the very least, discuss it, he advised. "It might help to attach a specific dollar amount or timeframe."
"Everybody is everyone else's lifeboat when it comes to hitting an iceberg," said Laurence Kotlikoff, economics professor at Boston University and president of MaxiFi, which offers financial planning software.
However, "it has to go both ways," Kotlikoff said. "Parents are providing a lot of support, and the kids have to realize that the quid pro quo here is that they're going to be expected to take care of their parents."
Having an open dialogue can help, he added. "Once that conversation gets going, it can continue for the next 40 years."