How many devices can I use to Activate Amex Pay for my Card(s)?

You can use 1 mobile device to Activate your Card(s) for Amex Pay. In the instance where you upgrade or replace your device, this remains true and you will either have to deactivate your Cards from Amex Pay on your old device or call American Express to deactivate Cards on your old device to be able to activate them on your new device.