A computer-implemented method for detecting potentially fraudulent cardholder transactions is implemented by a fraud detection computer system in communication with a memory. The method includes identifying a first home location for a first cardholder, identifying an expected range of travel relative to the first home location for the first cardholder when making a typical financial transaction in at least one merchant category, receiving transaction data associated with a first financial transaction, retrieving the first home location based on the cardholder data and a merchant location for the first merchant based on the merchant data, calculating a distance of travel between the first merchant location and the cardholder home location, comparing the calculated distance of travel to the expected range of travel, and flagging the first financial transaction as potentially fraudulent upon determining that the calculated distance of travel exceeds the expected range of travel.