Monitoring transactions by non-account holder

Monitoring a non-account holder seeking to perform a transaction with a financial institution includes receiving first transaction information including an identity of a non-account holder and a disposition of a first transaction between a first financial institution and the non-account holder. The first transaction information is stored in a transaction history data store. A portion of the first transaction information in the transaction history data store is later accessed when determining whether to perform a subsequent transaction with the non-account holder.