In general, a bank or credit union can't cash a check for six months if you make a timely stop-payment request in writing, according to the Consumer Financial Protection Bureau. If you make a stop-payment request by phone and don't follow up in writing, the bank or credit union can't cash the check for 14 days.

To cancel a check (technically called a "Stop Payment Order"), you must act before the check is processed and "clears" the banking system. In 2026, with the prevalence of digital imaging and faster clearing cycles, this window can be incredibly short—sometimes less than 24 hours. Once the recipient cashes the check and the funds leave your account, the bank can no longer "stop" it; you would instead have to pursue a private refund from the recipient. Generally, a stop payment order made over the phone is valid for 14 days, while a written request is typically valid for six months. It is important to note that most banks charge a fee (often between $25 and $35) for this service. Because checks are often processed as electronic transfers today, the moment the check is scanned at a register or via a mobile app, the "cancellation window" essentially closes, making immediate action vital.