Maybe you receive a letter stating you’ve won a foreign lottery but must wire back part of the enclosed check to pay taxes. Maybe someone offers to buy your online auction item but writes a check for more than the purchase price, asking you to wire back the difference. Or maybe you are offered a mystery shopping opportunity in which you make purchases with money from a provided check and then wire back the rest.

Whatever the pitch, don’t be fooled. The check is fake, and it’s a scam.

It works like this: The crook sends you a check, and makes up a reason for you to deposit it and wire some of the money back—such as paying fees on a sweepstakes you’ve won or returning the excess from a check for which they “accidentally” wrote the wrong amount. The checks look real, and often are printed with the names and contact information of actual financial institutions.

If you do as the scammer asks, it can take weeks for the fake check to be discovered—and when it is, you are responsible for paying back the lost amount.

Follow these tips to protect yourself from a fake check scam:

• Discard any offer that asks you to pay to claim a prize. A legitimate lottery would never ask you to pay for taxes, fees, or anything else—if you actually won, you would pay those taxes to the government.

• Instead of a check, consider using an online payment service or escrow service you trust to accept payment for online auction or classified items. These services often have built-in fraud prevention measures to protect both buyers and sellers.
• If you do accept a check, request one from a financial institution with a local branch so you can stop in to verify that the check is valid. If that’s not an option, call the financial institution the check came from—but do not use the contact information on the check. Find a phone number from the financial institution’s Web site or directory assistance instead.
• Throw away any offer that asks you to cash checks and wire money back as a mystery shopper or work-from-home employee. No legitimate employer would work this way.

If you have a check that makes you suspicious, consult the professionals at SIU Credit Union before cashing or depositing it.