Being approached on the street and asked to donate to a cause you have probably never heard of is a familiar, slightly awkward moment for many people. Whether moved by genuine generosity or simply hoping to avoid guilt, plenty of us drop a few dollars into the pot.

That everyday impulse is exactly what a growing number of scammers are now exploiting. Posing as nonprofits or charities, fraudsters are soliciting money from unsuspecting members of the public—and some are pulling off an old-fashioned bait-and-switch with payments. A donor may intend to give $20 using tap-to-pay, only for the scammer to change the transaction to $2,000 without the donor noticing, according to Kurt Knutsson, the tech expert behind the CyberGuy Report.

In essence, scammers are taking advantage of the newer tap-to-pay model, betting that donors will not notice when the number on the screen differs from the amount they had agreed to donate. The exposure has widened as contactless payments went from novelty to default: after adoption surged during the pandemic, Visa has said a majority of its face-to-face transactions worldwide are now completed with a tap, and the same portable card readers that speed up a checkout can just as easily be carried onto a sidewalk.

The damage extends well beyond individual victims. Every successful scam further erodes trust in philanthropies and nonprofit organizations—the very trust that millennials and Gen Zers so desperately want to maintain. According to Bloomerang's 2026 Giving Signals Report, conducted with The Harris Poll among more than 1,000 U.S. donors and 400 fundraising leaders in March, millennials and Gen Z care most about giving because it makes them feel as if they are "part of something." Even more than that, consumers want to trust organizations at a time when discretionary spending has become more precious amid inflation, stagnant wages, and a higher cost of living.

"Donors are ready to trust nonprofits, but they want to see the receipts more," Steve Isom, chief operating and financial officer of the nonprofit software company Bloomerang, recently told Fortune. "A bit more trust, but verified."

The Bloomerang report shows that 85% of active donors trust the organizations they donate to use funds effectively. But building that trust takes time, and increased scam activity can break down the confidence that legitimate philanthropic organizations and nonprofits need in order to succeed.

Authenticating a payment is not the same as trusting it

So how can consumers avoid scams and place their trust in real organizations? The disconnect starts with a subtle yet critical distinction: authenticating a payment and trusting it are not the same thing. A donor can approve a transaction on a card reader and still be deceived about what they are actually agreeing to, Mary Ann Miller, fraud and cybercrime executive advisor and VP of client experience at identity verification company Prove, told Fortune.

"The technology may work exactly as designed, but the problem is the manipulation happening around the transaction," Miller said.

"Fraudsters are increasingly exploiting trusted interactions and familiar behaviors rather than trying to break through security controls," she continued. "As these attacks become more convincing, consumers can't rely solely on intuition or a single authentication step to determine whether an interaction is legitimate or not." Her advice: pause and think before you tap to pay.

Recovering the funds is not guaranteed

Verification gaps matter even more once the money is gone, because getting funds back is never assured. Once a payment has been authorized by the donor—and was not made fraudulently by someone else—recovering those funds becomes even harder, Eva Velasquez, CEO of the nonprofit Identity Theft Resource Center, told Fortune.

Credit cards can offer a cushion, since cardholders can contact the issuer and dispute the charge, but instant payment methods do not carry the same protections, she noted. That cushion has long-standing legal roots: the Fair Credit Billing Act of 1974 gives U.S. cardholders the right to dispute billing errors, including charges that differ from the amount they agreed to pay. Consumer protections around faster payment methods, by contrast, are still evolving. In the UK, the Payment Systems Regulator began requiring payment providers in October 2024 to reimburse most victims of authorized push payment scams, a mandate that has no U.S. equivalent.

"That is going to be much more difficult to articulate to the financial institutions, and there is no guarantee that you will be made financially whole," Velasquez said.

The reason, she explained, is that "you did, in fact, authorize the payment," but "you did not check the final amount for the authorization."

Pick the charity yourself

Velasquez also encourages people to flip the dynamic entirely: choose the charity yourself rather than letting it choose you. Instead of reacting to whoever approaches with a card reader, donors should decide for themselves which causes they want to support, and then vet those organizations through third-party charity accreditation sites before donating. Long-standing options include Charity Navigator, CharityWatch, and the BBB Wise Giving Alliance's Give.org, each of which evaluates how charities raise and spend money. The Federal Trade Commission offers similar guidance, urging donors to resist pressure to give on the spot and to pay by traceable methods such as credit cards or checks rather than gift cards or wire transfers.

This story was originally featured on Fortune.com.