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I'm a European expat living in Asia. I usually hide my credit card at my apartment. However, I'm a bit scared about losing it when I carry it (wallet robbed or lost).

That's why I already scrubbed the CVV (security code) at the back of the card thinking that nobody could use it on Internet.

However, the thread What's the impact of disclosing the front-face of a credit or debit card? made me realize the CVV (security code) was not required on some websites (such as Amazon.com) when buying stuff.

So I'm wondering whether it would be a good idea to cut some digits of the card PAN (16-digit number which I know by heart) with a Stanley knife?

The only problem I can see is that a shop assistant could refuse me to pay with a "damaged" card. Nevertheless, I only use my credit card to get some cash, I suppose ATMs don't care about a "damaged" card (I guess they only get data from the chip).

Thanks for your help.


Update (21 hours later): Thanks all for your meaningful thoughts.

All of you (for the moment I got 4 answers: from Eric, Rory, Bruce and Lucas) think I shouldn't bother removing some digits from my card.

Some of you wrote I shouldn't worry because my bank would pay me back if somebody fraudulently use my card. True.

However, as this problem never happened to me, I don't know whether it's easy to be paid back: I guess my bank would ask for some good explanations about the theft and so on.

I forgot to mention in my question that my bank is Irish and my personal address for my card is my parents' address in France (as I travelled a lot). If somebody steals my card and buys an expensive camera on Amazon and get delivered in the city where I live in Asia, how could the bank believe it was not me?

That's why I thought it would help to remove some digits. I realize I was too naive and Eric's message made me understand that some thieves would be able to get the card number from its chip whatever I would do to the card.

In conclusion, I understand that cutting my card would only prevent "bad/inefficient" thieves (quite funny to write that) from using it.

As you advised I keep (for a long time) my bank "emergency phone number" at my fingertips in case of theft.

Thanks again for all your thoughts and advice.

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We forgot to mention, you can always get traveler's cheques. –  Eric G Apr 1 '13 at 15:55
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4 Answers

up vote 8 down vote accepted

A credit card contains the card number (also known as the PAN), it multiple ways. Even if you remove the raised digits, some thieves may had a card reader and can get this information off of the card swipe. If there are shops where they are using a rub method, they will need all of the digits anyway. You could just tell them the missing digits and they can write them down if its all offline. If they have a digital terminal, they will be typing in all of the digits one by one anyway and technically don't even need the card.

Old terminals without a chip and pin system can still work with a newer card.

Instead of mitigating the risk of your credit card being stolen, it might be more practical to look into the transference or risk. After being robbed, can you get to a phone and cancel your cards? Your card should have fraud protection to reverse the transactions. I cannot comment on whether the requirements are different in asia, but you should be able to have fraudulent charges reversed and a new card sent. You could also look into credit monitoring and other fraud protection services.

Edit:

I have also seen technology which replaces raised numbers with a digital display which you have to activate with a 4 digit pin on the card itself. I only recall two banks implementing such a technology. This doesn't appear to be exactly the same thing, but maybe in the future it will become more popular to have cards that dynamically re-write the mag strip like this or like this. Maybe you can get a new card from a bank with bleeding edge tech.

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Thanks Eric. The links you gave are very useful. Good to know that credit cards might be "safer" in the future. –  Jules Apr 1 '13 at 14:14
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Do not damage your card. Many places will refuse a card entirely if damaged.

Instead, just protect the card. Keep it with you if you are worried about your apartment being burgled. And keep it in an inside pocket if you are afraid of pickpockets.

And remember, if you are mugged, you can cancel cards and payments very quickly, and are generally insured against losses of this type.

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I was going to voice that as well. Keep in mind that most times people intentionally damage their cards it's in order to make it unusable by everyone, including themselves. –  Ekevoo Mar 31 '13 at 21:04
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Removing the first few digits (6 or less) may not help security at all. Visa cards all begin with a '4'. MasterCard card numbers begin with '51', '52', '53', '54', '55'. Discover and Amex have similar small numbers of prefixes. The next 4 or 5 digits are the "IIN" or "BIN" - these identify the bank or issuer of the card. Lists of IIN's are easily found. It may be possible to figure out the IIN based on the bank name on the card itself. You can't remove the final digit of a card number: that's a check-digit, calculated from all the previoius digits.

So, don't bother.

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As long as you don't harm the magnetic strip or the chip, there should be no trouble from a machine's point of view. However I wouldn't bother going through all that trouble for at least one good reason:

  • If your card is stolen, VISA will pay back your damages.

You are insured by the credit card companies against fraud, if you get defrauded you just have to call them and they will pay you back.

But as pointed out by Eric, the magnetic strip is a flaw which hasn't been patched by any CC or debit card company.

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