A payment device is provided for use in transactions such as credit purchases at a retail store. The device includes a non-volatile memory containing a set of multiple identifiers that are associated with a customer account. The multiple identifiers are also known to an agency that provides the customer account. The device further includes a processor operable to select one identifier out of the set of multiple identifiers for use with any particular transaction involving the device and the customer account. This identifier is then conveyed from the device, typically via a store terminal, to the agency that maintains the account.