Come January 1, 2018, debit card transactions are going to pinch a little less. To give a fillip to digital payments , the Reserve Bank of India ( RBI ) announced on Wednesday that it will rationalise the framework for merchant discount rate ( MDR ) applicable on debit card transactions.MDR is the rate charged to a merchant by a bank for providing debit and credit card services. In many cases, the charge is passed on to the customer by the merchant, saying that it eats into his margin. There are times when customers are asked to pay extra under the pretext that the swipe machine was installed by another bank. RBI has said that banks will have to ensure that the MDR levied on the merchant shall not exceed the cap rates irrespective of the entity deploying the card acceptance infrastructure at the merchant location.