Oxford Swindon and Gloucester Co-op has extended its fingerprint scanning trial to three stores and named the supplier of the service.
The retailer announced in January that it would be testing a voluntary fingerprint registration scheme at its convenience store at Summertown, Oxford, in an effort to improve self-checking-out there.
Customers are invited to register their fingerprint as verification of their age. This enables them to scan age-restricted products such as alcohol, tobacco and DVDs automatically, and negates the requirement for a supervisor to verify the customer's age.
The service is provided by US supplier Pay By Touch, which has several customers in the US, including supermarket chain Piggly Wiggly.
Oxford, Swindon and Gloucester Co-op group general manager Bill Laird said: 'The whole UK market is focused on the introduction of Chip and PIN technology to improve service and reduce fraud.
'This solution offers additional benefits, and challenges existing thinking regarding in-store transactions.'
The trial, which will be available at both manned and self-checkouts, will begin in the summer.