1. A method for securing a third party payment electronic transaction comprising: electronically maintaining a third party payment account between a payor device and a customer; programmably configuring a customer transaction device, the customer transaction device communicating with a payee transaction device; the payor device delivering an electronic transaction token from the payor to the customer transaction device; the customer transaction device generating a first validation code based on customer-possessed information including at least: the electronic transaction token and a first version of a transaction amount; and, including the first validation code in a first portion of an electronic voucher and transmitting to the payee transaction device; the payee transaction device adding a second version of the transaction amount in a second portion of the electronic voucher; the payee transaction device transmitting the electronic voucher to the payor device; the payor device receiving the electronic voucher and independently generating a second validation code for the customer based at least on the electronic transaction token and the second version of the transaction amount; and, validating by a processor a transaction amount for payment from the payor to the payee, the validation including comparing the second validation code with the first validation code.