A computer-based method for providing a loyalty identifier to a merchant using a payment network is described. The method includes storing data including at least one loyalty identifier associated with a cardholder enrolled in a loyalty program and a corresponding payment card identifier, receiving a first authorization request message for a payment transaction initiated by a first cardholder using a first payment card at an originating merchant, the first authorization request message including a first merchant identifier and a first payment card identifier, determining a first loyalty program associated with the originating merchant based in part on the first merchant identifier and the data stored in the memory, determining a first loyalty identifier associated with the first cardholder for the first loyalty program based in part on the first payment card identifier and the data stored in the memory, and providing the first loyalty identifier to the originating merchant.