A system and method for securing a Radio Frequency (RF) transaction using a RF identification device transaction device is provided. The invention uses the routing number and customer identifying information associated with a transaction account to secure a RF transaction. Specifically, the customer identifying information is included in an encrypted payload that is provided to a merchant point-of-sale device in a unused field of the RF data transmission. The routing number is provided in the ordinary field location of the data transmission typically reserved for the transaction account number. Additionally, the encrypted payload is provided in the unused field of the data transmission. The routing number is used to locate the corresponding encryption key for validating the RF transaction device, the transaction account and/or customer identifying information without the need for the reader to encrypt the customer identifying information before providing a transaction request to an account issuer.