Credit and debit card fraud alerts are up 15 percent from two years ago, according to a new report. But many are false.

Thirty-one percent of U.S. adults have received a fraud alert regarding a credit card, and 25 percent have received one concerning a debit card.

Thirty-seven percent who have been contacted about potentially fraudulent transactions say all of the transactions were legitimate purchases. Another 15 percent say “most” were legitimate.

Despite the popularity of text messages and emails, most companies will still call you by phone. Fifty-three percent of those surveyed say they received a phone call. Fifteen percent say they found out when their card was declined while trying to buy something. Just 14 percent received a text message and 12 percent got an email. And while many 18-26 year-olds do almost everything with their smart phones, only six percent say they were notified by text.

The study also showed that the more you make, the more likely you are to get an alert. Sixty-eight percent of those with an annual household income of $75,000 or more have received one alert, versus just 40 percent of those making less than $50,000. Only 26 percent of those with income under $30,000 were alerted.

The same is true for education levels. Sixty-five percent of college graduates received fraud alerts, compared with 49 percent who attended some college, and 25 percent who have a high school education or less.

“Fraudsters seem to be swinging for the fences, focusing their efforts on high-value targets,” said Matt Schulz,’s senior industry analyst. “And it’s not only more affluent and more educated households. Credit card limits typically exceed checking account balances. I think that’s why credit card fraud alerts outpace debit card alerts even though debit transactions outnumber credit transactions 2-to-1.”

Here's more info on the poll: