Originally Posted by
Mountain Trader
I have found that US credit cards sometimes work in the automatic machines, sometimes not. But the manned ticket windows can also add a week or month subscription to a Navigo and they do take US credit cards.
I think there is a euro threshold on the machines that requires a card with a chip. I was always able to use my US credit card to purchase a one-way trip to the airport or a carnet of metro tickets. I think I could even purchase a 1-week Carte Orange with my US credit card. However, I was never able to purchase a 1-month Carte Orange with my US credit card at the machines.