Like any of us, they thought they were writing a check to pay their taxes.
But their checks were altered and cashed by crooks instead.
According to the Nasdaq's Verafin company, which specializes in fighting financial crime, check fraud was up 11% in 2025 -- despite the total number of check transactions decreasing by 7%.
RELATED: Wells Fargo denies Bay Area homeowners $28K refund after check altered, cashed by mail thieves
Scammers and mail thieves are more active during tax season, but any time of year, there are precautions you should take to protect your payments.
First, opt for more secure checks and pens. Many banks offer checks printed on special paper that makes it harder to remove ink from it. There are also pens with indelible gel ink that doesn't respond to the chemicals often used to try to remove it.
When hand-writing your check, you should also draw a line in every empty space left after filling it in - taking up the room a crook could use to squeeze in additional writing.
RELATED: Taxpayers flood Napa Co. Tax Collector's Office after payments vanish in check fraud scheme
Once your check has left your hands, be sure to keep an eye on your bank account. AI-generated fake IDs and altered checking images have passed basic verification checks that would have caught manual forgeries in the past.
You should also check the online image of your cashed check as soon as it's available to make sure it went to the right recipient. You usually only have a short window of time where you can report the fraud to your bank.
And of course, you can always make your payments online, skipping the pen and paper entirely.
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