A system for building a data table of travel-related data and using the data table to reduce false declines when processing payment transactions is provided. The system includes a travel identifier (TI) computing device configured to receive transaction data that includes travel-related data and cardholder identifiers, the transaction data associated with transactions initiated by a cardholder, identify the travel-related data for the cardholder, and build a data table for storing one or more records within an itinerary data source using the travel-related data. The TI computing device is also configured to receive current transaction data for a current transaction initiated by the cardholder including a current transaction location and a current transaction date. The TI computing device is further configured to authenticate the current transaction data by electronically matching the current transaction location and the current transaction data to the data table stored in the itinerary data source.