Biometric authentication of pre-staged self-service terminal transactions

A method comprising:

• defining input for a purchase transaction that is to be subsequently completed on a Self-Service Terminal (SST) by a mobile device app that executes on a mobile device of a customer, wherein the mobile device is operated by a customer associated with the purchase transaction;
• initiating a transaction by transmitting, via a first wireless communication device of the mobile device, data defining the purchase transaction to pre-stage the purchase transaction on the server for download by the SST upon authentication of an account holder of an account, wherein the customer is the account holder of the account;
• establishing a communication link with the SST by connecting, wirelessly via a second wireless communication device to the mobile device;
• authenticating the customer by receiving, via the second wireless communication device of the mobile device, biometric data provided by a biometric reading device of the SST to authenticate the customer as the account holder who is operating the mobile device for the purchase transaction at the SST;
• matching, on the mobile device by the mobile device app, the received biometric data with stored biometric data of the account holder by:
• retrieving the stored biometric data stored on the mobile device;
• and
• comparing the received biometric data and the retrieved stored biometric data to identify a match and determining a confidence level thereof, wherein the stored biometric data stored on the mobile device is stored securely by the mobile device app and is not accessible and never shared by the mobile device app;
• finalizing the purchase transaction upon matching the received biometric data and the stored biometric data of the account holder on the mobile device, wherein finalizing further includes transmitting an authentication message via the second wireless communication device to the SST, wherein the transmitted authentication message includes an account identifier for the account, a security code or security certificate, and a transaction identifier for the purchase transaction, wherein transmitting the authentication message further causes the SST to receive, the data defining the purchase transaction from the server and causes the SST to process the data defining the purchase transaction on behalf of the customer on the SST, wherein the SST is an automated teller machine;
• and
• flushing a secure memory of the biometric data on the SST upon completion of authentication ensuring the biometric data of the customer is not stored or compromised on the SST.