Abstract: The methods and systems described herein include a data gateway adapted to automate payment reconciliation between a buyer and a supplier of goods and services. The data gateway can be configured to receive and validate payment instructions for one or more payment transactions between the buyer and the supplier to select a payment method based on the payment instructions. Transaction request messages are generated and transmitted to a payment processing network or a payment transfer system associated with the selected payment method. A payment reconciliation message can then be generated and transmitted by the data gateway to a buyer adapter associated with a buyer computer system and a supplier adapter associated with a supplier computer system when the data gateway receives payment authorization from the payment processing network or payment transfer system.