[tomp]

My experience from the US is... interesting. I tapped-and-paid $700 (not a typo) when visiting NY... and American Express had no idea I was in the US (unless they cooperate with US Border Controll). In the UK, I'm limited to 30 GBP.

[dandandan]

Did you buy the ticket with your American Express card? The data transmitted by the merchant (airline) includes some basic itinerary information.

[tedmiston]

That would be awesome if the CC provider automatically created a travel notification for you upon booking.

[tjohns]

Some do.

Many airlines transmit level 3 purchase data as part of the credit card transaction, which will contain your complete itinerary -- which can be fed into the bank's risk system.

[lostlogin]

The next few decades of adverts that I couldn't unsubscribe from would be less than awesome though.

[saryant]

Amex already takes this into account.

[tomp]

No, I haven't, that's exactly the point! And I think that's the first transaction I've made in the US..