A debit card takes money straight from your bank account. A credit card uses the bank's money, and you pay it back later. Both work in the same card machines, but the protection is different.
If your card is stolen or used by someone else
Federal law limits what you lose:
Credit card: you pay at most $50 for charges you did not make. Most card companies charge you $0.
Debit card: you pay at most $50 if you report it within 2 business days. Up to $500 if you report it later, within 60 days after your statement. After that, you could lose everything taken.
With a debit card, the money leaves your account first. You wait for the bank to investigate and return it, and rent can bounce in the meantime. With a credit card, you dispute a bill, not missing cash.
Lock or freeze the card in your bank app right away.
Call the number on the back of the card.
Write down the date, time and the name of the person you spoke with.
Check your statement for every charge you did not make.
Disputes for bad purchases
If you pay by credit card and the item never arrives or is not what you paid for, you can dispute the charge with the card company. Do it in writing within 60 days of the statement. Debit cards have weaker rights here, so use a credit card for online shopping and travel.
Holds: money that disappears for a few days
A hold (or "authorization") reserves money before the final amount is known.
Gas stations: when you pay at the pump, the station may hold more than you spend. The hold drops off when the real amount posts, usually within a few days.
Hotels and car rentals: they hold the room or rental cost plus extra for damage or extras. It can stay for days after you check out.
Restaurants: the hold may grow when the tip is added.
On a debit card, a hold blocks your real money. On a credit card, it only uses some of your limit. This is another reason to use a credit card for hotels, car rentals and gas.
Using a debit card at a hotel, then having your rent payment fail because of the hold.
Waiting weeks to report fraud on a debit card. Report the same day.
Typing your PIN where others can see it. Cover the keypad.