Abstract: A method and system to reduce card transaction fee while enabling the payment from dynamically mapped retail cards. Being a mapping and API based solution, technical integration with any bank is much easier with very less cost while enabling the easy future enhancements. With this Solution customer will map all his retail card to any one credit card on app and while making the payments solutions will enable bank to take payment from the respective retail card for retailer. With this mapping-based solution customer will get same functionality, if due to any reason he is not able to use his mobile for payment and use the credit card mapped.