Abstract: Disclosed are exemplary embodiments of systems and methods for analyzing declined payment account transactions. In an exemplary embodiment, a method generally includes accessing, by a computing device, a declined transaction associated with a payment account, and applying, by the computing device, at least one rule to transaction data associated with the payment account and/or transaction data associated with a merchant involved in the declined transaction. The method also includes, based on the at least one applied rule, appending, by the computing device, a fraud accuracy tag to the declined transaction in a data structure, where the fraud accuracy tag is indicative of whether the decline of the transaction is a true positive decline or a false positive decline, whereby the fraud accuracy tag is suitable to provide insight into accuracy of a fraud strategy implemented in connection with the declined transaction.