I have a credit card that’s getting worn out. I’ve found putting it inside a thin plastic bag often makes it work better in a scanner. I’ve also seen other people use this trick.
Why does this work?
I googled to find out, and lo and behold…Cecil answers!
(Second letter.)
Answered. Science questions are good but practical answers are better. Call your credit card company and tell them you need a replacement card. You will get one in 3 - 5 business days with an extended expiration date.
Cecil’s answer is a good one, but his closing comment (“God forbid the clerk should have to punch in the numbers by hand”) misses a significant point.
Many (most?) merchant card services companies charge the store an extra fee when the numbers are entered by hand. With our old contract, I think it was half a percent. So if the card didn’t scan, it didn’t just mean a bit more of the clerk’s time punching in the numbers, but potential errors and cash out of the store’s profit.