A check that left a Los Altos mailbox may not be the check a bank eventually pays. Mail theft has targeted mailboxes outside the Miramonte Avenue post office, a concern for people who mail checks.
The notice is a Nov. 14 Facebook post the department titled "CHECK FORGERY UPDATE."
Checking account activity and considering electronic payment are among general precautions against check fraud.
Look at the Image, Not the Memory
The useful distinction is easy to miss if you only watch the balance. A payment that cleared is not proof that it cleared as written. Reviewing bank activity can help catch a problem.
An intercepted check can be altered before it is cashed. Remembering what you wrote is not the same as checking what the bank paid.
Los Altos Has Been Here Before
This is familiar local trouble, even as a separate chapter from the Miramonte notice. On Aug. 2, 2024, NBC Bay Area reported that police were investigating a rise in mail theft and that thieves were targeting USPS blue mailboxes downtown.
Los Altos Online has reported that police urged vigilance after multiple local check-forgery cases. The mechanism it described is blunt: intercepted checks "are then chemically washed and altered before the suspects attempt to cash them."
Sgt. Steve Spillman has also described "a spike in stolen mail and checks from the Los Altos Post Office in downtown Los Altos," in a separate Los Altos Online report. Downtown collection boxes and a named post office have already been part of the city's mail-theft problem. Mailboxes outside the Miramonte Avenue post office have also been targeted.
A $118 Check, Plus $4,000
The FBI has described the method without much poetry. In material dated Jan. 27, 2025, the bureau said check theft happens in several ways, and that fraudsters use check washing or other "cooking" techniques to alter checks or create counterfeits so they look legitimate.
Bay Area cases show what that cooking does to the arithmetic. ABC7 reported that an elderly San Francisco woman lost $14,000 in a wave of mail theft and check-washing fraud. Thieves stole a $118 check she had mailed, "tacked on their name and added $4,000 to the amount." A South Bay resident said a thief stole his $100 check and wrote it for $6,000. An alert bank manager stopped that one.
Recovery, in the San Francisco case, was partial and slow enough to need a nudge. After ABC7 asked BMO about a third check, the bank refunded $5,137. A reporter's question is not a claims process. It is a reminder that a rewritten check can clear before anyone who wrote the original amount has a reason to look.
Call First, Then Skip the Box
Anyone who recently mailed a check in Los Altos can watch bank activity for signs of check fraud.
Electronic payment or another method avoids sending a paper check through the mail.
