A computer system including a processor, in communication with a database, programmed to identify a plurality of billers from the database, including biller information, and receive a payee file including payee information identifying a payee which issued a bill to a payor. The processor determines an approximate match score for each of the billers in a first set of billers of the plurality of billers by comparing payee information to biller information and identifies a candidate list of billers from the first set of billers having an approximate match score indicating a likelihood of matching the payee information. The processor adjusts the candidate list of billers by altering the match score of at least one candidate biller by comparing a payee account number of the payee information to an account mask associated with the candidate biller and generates an output file of candidate biller information from the adjusted candidate list.