How long do you have to stop a check that's been deposited?

You typically have to request a stop payment on a check before it is cashed or deposited. The time frame can vary by bank, but generally, you should act as soon as you realize the need to stop the check. Some banks may allow you to stop a check for up to six months, while others might have a shorter period. Always check with your bank for their specific policies and procedures regarding stop payments.