Methods, systems and device for verifying a transaction in a loyalty or advertising system are described. One such method includes: receiving, at least one processor, transaction data associated with a transaction between a customer and a merchant; determining, at the at least one processor, from the transaction data whether the customer and the merchant are associated with the loyalty or advertising system; and upon determining from the transaction data whether the transaction corresponds to a reward or advertisement, triggering the redemption of the reward or advertisement.