What tips the credit card fraud department that a card is being used fraudulently?

My credit card company looks at location and “unusual” charges. So if someone buys something that’s really different from our usual purchases it gets flagged. For location, they look at our other recent purchases to see if they’re in the same area.

@Seaofclouds The charge on mine was only $6 and some change, which wouldn’t be strange for me. But yes, if they have a charge for $6.00 in town A, and 30 minutes later they have a similar charge in town B, which is 500 miles away, that would be a flag. I wonder if they have a computer program that catches that?

When I was in customer service at CellOne I had a customer call in, just freaking out, saying that she had roaming charges in places she had never been. Well, we used to get bogus calls like that all the time. They’d given the phone to someone else, or they were just trying to get out of the charges.
Well, I looked closer. Yeah, there were calls being made on her ESN, minutes apart but hundreds of miles away. That was the first case of ESN stealing I’d had. It was interesting.

In my case, I lost mine. It turns out that after having paid for my gas at the local statio, had put it in a jacket pocket with a hole in it. The card slipped out. By the time I discovered I didn’t have it, an hour or so later, someone had picked it up from the ground next to the pump and kindly called Cap. One Master Card to report that he had found it. The credit card people automatically canceled and then called me.

They gave me the name of the good samaritan, but he was not local. No good deed, I guess. He might have just looked me up in the local phone book, but he didn’t.

But that’s a case of human intervention and a physical card. I’m just wondering how, out of millions and millions of transactions, the minor ones, like mine, would be caught because I know humans are not reviewing each and every transactions. There must be an ap for that.

Wish I’d asked what kind of program they use.

On the rare occasions that I purchase something that is outside my normal charge range, like a new laptop or a hot water heater, for example, I call the customer service number ahead of time and alert them.

Hm. Well, that wasn’t outside my normal price range, either.

@Dutchess_III: Yet, on the other hand, in your case it would be possible that you (the credit card holder) did take a trip out of the country. The card company would very likely not know that.

That’s my point @jca. Something flagged them that my card was used in a neighboring state, Nebraska. I mean, I’d used the hell out of it two weeks before in Oklahoma, also a neighboring state. What flagged them in the Nebraska case and not Oklahoma?