Abstract: The invention relates to an assembly for handling transactions between a merchant and a consumer, comprising: —a cash register for generating and sending invoice data representative of the one or more products and/or one or more services relating to a transaction; —at least one payment terminal for generating and sending an electronic transaction order; —a payment system for electronic transfer of the transaction amount from the bank account of the consumer to the bank account of the merchant; —a transaction order processor for electronic clearing and settlement of the transaction amount associated with the transaction order, —a payment management system adapted to receive the invoice data and the electronic transaction order and to store at least a part thereof on a storage medium, wherein the payment management system is further adapted to control a transaction order processor in order to perform the transaction on the payment system.