A national warning was issued by the Federal Trade Commission on Thursday, warning people of card skimmers.
Skimmers are devices illegally placed on things like gas pumps and ATMs that "skim" a credit or debit card's information, giving criminals access to your bank accounts.
The criminals then use the data to make online purchases or clone cards for use in person.
"You won't know your information has been stolen until you get your statement or an overdraft notice," the Federal Trade Commission said.
While skimmers aren't new, the commission warns advancements in technology has made them smaller and harder to find. They can even be hidden inside a gas pump.
The following tips are some ways you can avoid becoming a victim:
• Make sure the gas pump panel is closed and doesn't show signs of tampering. Many stations now put security seals over the cabinet panel. This is part of a voluntary program by the industry to thwart gas pump tampering. If the pump panel is opened, the label will read "void," which means the machine has been tampered with.
• Take a good look at the card reader itself. Does it look different than other readers at the station? For example, the card reader on the left has a skimmer attached; the reader on the right doesn't.
• You can try to wiggle the card reader before you put in your card. If it moves, report it to the attendant. Then use a different pump.
• If you use a debit card at the pump, run it as a credit card instead of entering a PIN. That way, the PIN is safe and the money isn't deducted immediately from your account. If that's not an option, cover your hand when entering your PIN. Scammers sometimes use tiny pinhole cameras, situated above the keypad area, to record PIN entries.
• Monitor your credit card and bank accounts regularly to spot unauthorized charges.
• If you're really concerned about skimmers, you can pay inside rather than at the pump. Another option is to use a gas pump near the front of the store. Thieves may target gas pumps that are harder for the attendant to see.
If your credit card has been compromised, report it to your bank or card issuer. Federal law limits your liability if your credit, ATM, or debit card is lost or stolen, but your liability may depend on how quickly you report the loss or theft.