a system for implementing a method that books and pays a retailer having a pos connected to a transaction server storing confidential user information including a retailer identification , a user code , and a user wireless device phone number . the method includes : receiving at the transaction server , from the user wireless device which can be a cell phone , an sms containing a retailer identification ; reading at the transaction server the phone number of the wireless device communicated by the carrier transporting the sms ; authentifying the phone number and retailer identification with the stored confidential user information ; sending the user confidential information to the retailer pos . the user enters on the pos the user code . the pos reads and authentifies the user code with the user confidential information received from the transaction server . the retailer enters the payment information on the pos and sends it with user information to the transaction server .