asked Her Majesty's Government:Whether, when credit cards are used, a legally-binding contract is established only when the authorisation slip is signed by the purchaser and not when the card is swiped through the machine. [HL773]

A number of different contractual relationships arise when a purchase is made using a credit card, and I have confined myself in this response to the question of the contractual relationship between the buyer and the seller in respect of a sale of goods.In this context, the question of precisely when a legally binding contract is made will depend upon the principles of the law of contract, including those relating to offer and acceptance. The application of these principles will vary according to the facts of each case, and the time of payment (whether determined by reference to swiping a card or signing a slip authorising payment or some other event) will not necessarily be a material factor in pinpointing the time at which a contract was made.