The most common way checks are stolen is through the U.S. mail, including blue boxes situated on street corners, USPS facilities, and residential mailboxes. According to USPS’s findings, approximately 25,000 blue boxes were targeted in the first half of 2023.

 What is Check Washing?

Criminals can easily steal paper checks sent through the mail by fishing them out of USPS mailboxes or your personal mailbox. They may even resort to robbing postal workers to find checks. Once they have your check, they use chemicals to “wash” it, changing the amount or payee to steal money from your account. If you’ve sent a check that was paid, but the recipient never received it, you may have fallen victim to check washing.

 How to Protect Yourself?

  • If a bank provides an image of a cashed check, review the back of the check to ensure that the endorsement information is correct.
  • Consider using e-check, ACH automatic payments, and other electronic or mobile payment methods.
  • Use indelible black ink pens to make it harder to wash checks.
  • Review copies of your checks for alterations through Online Banking.
  • Regularly review your bank activity and statements for errors.
  • Avoid leaving blank spaces in the payee or amount line.
  • Drop off mail in blue collection boxes before the last scheduled pick-up time or directly at your local Post Office. Do not leave your mail in your mailbox overnight.


If you fall victim to check washing, immediately file a report with: The United States Postal Inspection Service, your local police department or your financial institution.