Are my credit cards still valid if I punch a hole in it (not in the magnetic strip, obviously)?

I’m not a banker, so don’t count this as a totally authoritative answer, but I would think that punching a hole for a keyring would NOT in any way invalidate a card. Why would it?

As you said, don’t damage the magnetic strip, but popping a hole in the bottom (under the raised letters) isn’t going to harm anything.

Try it!. And of course almost every credit card issuer has a website that lets you do a card reorder in case it is a problem.

It’s not going to be a problem for the simple reason that these days almost no one else has to handle your credit card. About the only time I don’t swipe my card myself (or use it over the phone or computer) is when I use my AmEx card at a restaurant. That’s pretty much the only time that someone else rings up a charge for me. So, since no one else normally even sees my card, its appearance can hardly matter to them.

What I would be concerned about, however, is the durability of the magnetic strips if the cards continually rub against each other or are jostled in a pocket or purse with keys, pens and other potentially damaging metal objects.

Edit: I would be sure to double-check any place that I planned to punch a hole in a card, though. You’ll probably want the hole in the same place on every card, so they appear neat on the key ring or holder. So check to make sure that you won’t damage the raised lettering or numbers on any card, the magnetic strip on any card, the “security number” on any card, or even the contact telephone numbers or signature strip on the back of any card.

I don’t think it invalidates it, but I do think there will be cashiers wo won’t accept it. Same way some cashiers won’t take a torn bill, or a bill missing a piece. They just assume it is no good, or worry they are not supposed to accept it as tender.

Places you swipe the card yourself you obviously won’t have a problem, unless they check ID and your card. Where I live about 75% of stores check ID. Nowhere else does this happen and I have lived and travel to several states regularly.

Also, you should never have your name on your key ring in my opinion. I know women have their name in their purse and their keys are often in the same place, so if you are going to have it in your purse anyway, I guess my point is moot. But, it is so easy to get your address from your name, having your house key with your name just gives a thief an easier time to rob you.

To clarify, I mean check ID when you use your credit card. Where I live they check the majority of the time.

As a cashier, I have swiped cards with parts of the card missing, info rubbed off, and cards that have been cracked nearly in half. As long as the magnetic strip and the important info is intact, you should be fine.