Overall, 50 percent of respondents said they carry cash with them less than half of the time they are out. When they do carry it, 76 percent say they keep less than $50 on hand and nearly half say they keep less than $20.
About 46 percent say they use cash less than eight days each month and 5 percent say they never use it.
One reason for the shift away from paper, financial advice website NerdWallet experts speculate, is the growing use of person-to-person payment apps, like Venmo, that allow users to digitally swap funds.
Another reason: e-commerce in general. "Rather than going to the grocery store and paying with cash, for example," NerdWallet says, "people now order groceries online and pay electronically. These trends, combined with the now-widespread use of debit [and credit] cards, have made carrying cash a rarity for many."
In fact, when given a choice between paying someone with cash or with an app, the survey found 47 percent of respondents would choose the digital option.
By generation, not surprisingly, millennials most prefer going online: 49 percent say they have made virtual payments compared to 44 percent of those in Generation X and 32 percent of baby boomers.
And 48 percent of men have used payment apps in the last six months versus 38 percent of women.
Still, not all Americans are sold on e-transfers. According to the survey, done before the launch of U.S. Bank's digital payment app Zelle, only 43 percent of respondents reported making a payment through a person-to-person app.
Most cited security risks, additional fees and lack of immediate access to funds as barriers.
There are also good arguments for carrying cash. For starters, since it's "more painful" to watch your money disappear, you could find that . Especially since, with surcharges and fees, like the extra dollar or so a movie theater charges you to buy tickets in advance with a card, you often have to pay extra when you use plastic.
Bills can also come in handy in an emergency or if you lose your credit or debit card.
Convenience continues to make digital payments an attractive option for many. And, according to NerdWallet, there is no doubt Americans' spending habits are changing, thanks to technology: "Sending money has become virtually as easy as texting, as social media apps have added payment options." For instance, Facebook now allows you to send your friends money in honor of their birthdays.
"If you hate to carry cash and are interested in the emerging array of payment apps, there are plenty of options out there," the site says, but "be sure to compare all the various features, including transfer speed, fees, security and user experience. In the end, some people may always prefer keeping some cash on hand."
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