In a survey of more than 2,000 Americans, U.S. Bank found that 50 percent of respondents said they carry cash with them less than half of the time they are out. When they do carry the green, 76 percent said they keep less than $50 on hand and nearly half have less than $20.

Fewer and fewer adults are using printed or minted U.S. currency at all any more. About 3 in 10 Americans said they make no purchases with cash in a typical week, up from a quarter in 2015, according to the Pew Research Center. At the same time, the share who said that all or nearly all of their purchases are made using cash fell to 18 percent from 24 percent in 2015.

Cash is no longer king, according to more and more consumers.

Not surprisingly, millennials are paving the way among people ditching bills and coins in favor of credit, debit and digital payments, through apps like Apple Pay, Venmo and Zelle. In fact, more than 1 in 10 millennials use their digital wallet for every purchase, according to a separate report by Experian — especially on food, rent and Uber rides.

Overall, about one-third, or 34 percent, of adults under the age of 50 make no purchases in a typical week using cash, compared with 23 percent of those ages 50 and older, Pew found. The Pew Research Center surveyed more than 13,000 adults in September and October of last year.

Wealth also plays a role. Adults with an annual household income of over $75,000 were more than twice as likely as those making less than $30,000 to say they do not make any purchases using cash in a typical week.

On the flip side, lower-income adults were about four times as likely as higher-income adults to say they make all or almost all of their purchases with cash.

But don't count those paper greenbacks out just yet. Cash still remains the most frequent method of payment in the country overall, representing roughly 31 percent of all consumer transactions, more than electronic, credit, debit or checks.

That may prove problematic as more businesses, including Starbucks and Shake Shack, experiment with becoming completely cashless establishments. (Lawmakers working to pass bills that would require retailers to accept cash allege that the growing cashless trend discriminates against low-income customers.)