When you check into a hotel, the desk clerk may inform you that they have to take an "imprint" of your card. Wait, what?
Taking an "imprint" means putting your credit card information on file so that if you raid the minibar, order room service or smash some furniture with the rest of your band, the hotel can charge the cost to your card. If you've reserved the room with a credit card, the hotel might just ask if it can use that one for the imprint. Or it may ask you to provide a card for them to use.
In general, there's no additional risk to your credit card information in providing an imprint, and you may have no choice anyway: The hotel just might not give you a room unless you provide a card for the imprint.
What gets 'imprinted,' exactly?
The term "imprint" comes from the days before credit cards had their data encoded on magnetic strips on the back or, later, EMV chips embedded in the card itself. Back then, all the important card info — cardholder name, card number, expiration date — was embossed on the card in raised letters. (Some cards today still have those raised letters, but there are fewer and fewer of them every year.)
When you bought something with a credit card, the merchant stuck the card in a little mechanical device, placed a paper sales form on top of it and then ran a slider over both of them. The info from the card was physically imprinted onto the paper form by the pressure from the slide. That paper form was the only record of the sale — electronic card readers weren't in use yet. The sale wasn't final until the merchant actually filled in the rest of the form, had you sign it and sent the form to a bank. If the merchant threw away the form, it was as if the transaction never happened.
Hotels would take a paper imprint of a card from incoming guests. If the guests left without incurring any "incidental" expenses, the hotel just threw away the imprint (hopefully they shredded it first). The technology has long since changed, but the terminology remains: Taking an imprint means taking down your card information in case it's needed later.
Is leaving an imprint safe?
Credit card information taken as an imprint must be stored in accordance with industry security standards. That means the hotel can't just write it down on a slip of paper at the front desk. In the days of paper forms, imprints had to be stored in a secure location with limited access. Nowadays, everything it electronic, and there are no paper forms to keep track of.
When a hotel takes an imprint today, what usually happens is that the hotel submits the card to the payment network to make sure it's valid and then pre-authorizes a transaction for some nominal amount — maybe $1, maybe $100. If you log into your account, you'll see it there as a pending charge. This is the equivalent of putting the imprint in the safe.
If you wind up with incidental charges, the hotel will amend that authorized transaction for the correct amount and submit it — the equivalent of sending the paper slip to the bank. If you don't incur any charges, the hotel doesn't submit anything and the pending transaction is deleted. The slip gets shredded.
So the security in place for an imprint is essentially the same as for a regular transaction. Hand over your card with confidence that it won't be charged unless you can't stay out of the minibar.