When you swipe or insert your credit card into a card reader, the card reader receives information like your account number and credit limit. If the magnetic strip is damaged, the card reader won’t be able to retrieve the information it needs to approve the purchase. The process of a magnetic strip losing its ability to communicate this information is called demagnetization.
Scratches and general wear are common causes of demagnetization, but prolonged exposure to magnets can also ruin a card’s magnetic strip. Fortunately, you don’t need to worry about magnetic damage if your credit card has an EMV chip. This newer chip technology has nearly replaced magnetic strips and isn’t susceptible to magnet damage.
Do magnets mess up credit cards?
The data stored on the magnetic strip of your credit card includes your name, account number, expiration date, credit limit, card number and card usage information. The strip also carries an encrypted pin, country code and information about currency units.
Magnets can erase or scramble that information, which can interfere with your ability to make a purchase. However, a magnet’s exact effect on a credit card depends on a variety of factors, including the length of exposure and distance from the card.
The longer a card is exposed to a magnet (usually an inch or closer), the more likely the magnet is to erase information on the magnetic strip. Thankfully, it may take multiple, long-term interactions with a magnet to cause harm to your card.
Types of magnets that may harm credit cards
Magnetic money clips and cell phone holders can make transporting your cards more convenient, but they may cause damage after some time. In some cases, money clips have magnets on both sides, making it difficult to create a necessary buffer or distance between your card and the magnets.
Leather product company Moore & Giles recommends its customers use money clips for cash, rather than credit cards. Even the leather strip on certain products isn’t enough to wholly prevent demagnetization.
Cellphones, on the other hand, have very small magnets inside, meaning the outer shell of the phone can act as a buffer between your cards and keep them safe from potential damage.
In general, it’s better to keep your cards in a wallet that will provide some protection from demagnetization. It’s also good practice to face card magnetic strips away from any magnets that may be around, like those on a refrigerator or purse clasp.
Other types of card damage
Keeping your card’s magnetic strip away from magnets is one way to take care of your credit card, but magnets aren’t the only cause of damage.
Magnetic strips and EMV chips can sustain damage from being scratched, for example, by a key or coin. These scratches can make it difficult for card readers to pick up the information on the magnetic strip and can cause a card to eventually be unusable. Liquids may also damage EMV chips.
EMV chips are magnet-safe
Nowadays, you don’t have to worry much about magnets damaging your credit card because magnetic strips have become nearly obsolete. Instead of a magnetic strip that you swipe, most credit cards now have an EMV chip that you insert into a card reader or even use to pay contactlessly.
Luckily EMV chips aren’t affected by magnets. However, scratches or prolonged exposure to water can cause damage or make them stop working altogether.
What to do if your card is damaged
If your credit card becomes damaged, contact your issuer right away to report the issue. Your issuer may be able to troubleshoot the problem with you to get the card working again. If that isn’t possible, the issuer can at least offer you a replacement card.
Replacement cards usually take about three to seven business days to arrive. If you need to use your card before then, you can ask your issuer to expedite the shipping of your replacement card or possibly request a virtual card.