A whopping 76% of Americans have "at least one regret" about the way they've handled their money, according to personal finance website Bankrate's May Financial Security Index.

The study includes more than 1,000 respondents.

Of those with a financial regret, 56% say it has to do with savings. That includes 27% who say they didn't start their retirement savings soon enough, 19% who didn't contribute enough to an emergency fund and 10% who wish they would have saved more for their children's education.

It's apparent that "regrets about savings are head and shoulders above other regrets — even about debt," Greg McBride, Bankrate chief financial analyst, says in the report. "Americans are under-saved for both retirement and emergencies, and are increasingly aware of it."

Perhaps not surprisingly, baby boomers, ages 55 to 73, were most likely to cite not saving for retirement early enough as their top regret, as 33% chose that option. That's compared to 23% of those in the Silent Generation, ages 74 and older, and 22% of Generation X, ages 39 to 54, who say the same.

As for younger generations, most regret not putting enough money toward an emergency fund: 19% of both older millennials and those Gen Xers say they wish they would have saved more.

Other studies draw similar conclusions: Northwestern Mutual surveyed more than 2,000 U.S. adults and found a third have less than $5,000 stashed away for retirement while 21% have nothing saved at all. According to the Federal Reserve, a third of Americans don't have enough to cover even an unexpected $400 expense without selling something or borrowing money.

Still, retirement savings and emergency funds aren't Americans' only financial concerns. Per Bankrate's findings, 16% of respondents feel they've taken on too much credit card debt, 11% say they have too much student loan debt and 7% say they've bought more house than they can afford.