A method for processing a transaction of a communications terminal, asking a server, through a communications network, for processing of a transaction involving the use of payment data. The method is implemented within the communications terminal. The method includes: transmitting a request for obtaining a certification code to the payment method whose data is used for the transaction; receiving the certification code coming from the payment method; inserting the certification code into a transaction data structure; transmitting the transaction data structure to the server; and when the certification code received by the server is valid, receiving a piece of data representing the validation of the transaction by the server.