I have my cards email me every transaction so that I can spot these events quickly. Ironically, after I set that up, my number hasn't been stolen. It had been stolen 4 times previously. My favorite was when the fraud agent asked me, "Did you purchase 150 lbs of concrete in Mexico yesterday?" Just after he had verified I was traveling somewhere else.
I get push notifications from the Chase app every time my card is used. Just last night I caught a fradulent transaction that way...the merchant name was "ONLINE SHOP ORDER", which was interesting since it that name is seemingly a merchant account set up explicitly to mask fraudulent transactions. Having push notifications is also a great way to remember to cancel unused recurring subscriptions.
I'm always super impressed with the speed that the notifications come through when I'm checking out somewhere. I'll get a notification on my phone over a flaky 4G connection before the CC reader pops up the 'Approved' screen. Lot of computers talking to each other to make that happen...
Similary when my card was canceled last night after the fradulent transaction I got a notification before I even got off the phone with the fraud agent that the replacement cars number had been added to my Apple Pay. Pretty cool!
