According to BankRate.com, 78 percent of Americans now carry less than $50 in cash.
50 percent say they carry less than $20, and 9 percent don't carry cash at all.
"People like the convenience of plastic and more transactions are going to continue to migrate that way," said Greg McBride, with BankRate.com.
More retailers accept both cash and card, but some still rely on the dollars and coins to do all their business.
Experts say it is possible that customers will push to a card-only society in years to come.