Abstract: A secure transaction card system and method utilizes a transaction card and an authentication device. The transaction card includes a first electrical contact, a power supply device, a card memory that stores a card identifier and a magnetic strip provided with a thin film magnetic write head in electrical communication with the power supply device. The authentication device includes a housing with an access slot for the card, a power source, a second electrical contact structure, an authentication processor in electrical communication with the second electrical contact structure and the power source, and a programmable memory storing account information corresponding to the transaction card. When the transaction card is mated with the authentication device, the processor causes account information to be written onto the magnetic strip so that the card can be used. After an interval of time, electrical charge is drained so that the card is inoperable.