Abstract: A method of authorizing a payment transaction is described. The method comprises receiving data relating to a customer's transaction card, and data relating to an original amount of the payment transaction; presenting the original amount data to the customer such that a gratuity amount can be determined and in response thereto receiving data relating to the gratuity amount; establishing a link with an acquirer via a telecommunications network and seeking online authorization for the payment transaction by transmitting the transaction card data and data relating to a value of the transaction and generating and providing receipt data to the customer. The transaction value comprises the gratuity amount and the original amount and the receipt data confirms authorization of the payment transaction at the transaction value when the transaction has been authorized. A method of authorizing concurrent payment transactions, such as may be generated by multiple mobile handsets and a base terminal, is also described.

Abstract: A method of authorising a payment transaction is described. The method comprises receiving data relating to a customer's transaction card, and data relating to an original amount of the payment transaction; presenting the original amount data to the customer such that a gratuity amount can be determined and in response thereto receiving data relating to the gratuity amount; establishing a link with an acquirer via a telecommunications network and seeking online authorisation for the payment transaction by transmitting the transaction card data and data relating to a value of the transaction and generating and providing receipt data to the customer. The transaction value comprises the gratuity amount and the original amount and the receipt data confirms authorisation of the payment transaction at the transaction value when the transaction has been authorised. A method of authorising concurrent payment transactions, such as may be generated by multiple mobile handsets and a base terminal, is also described.