The cash & carry giant is testing the technology in its Kettering, Lancaster and Lincoln depots. Customers are given a scanner gun, which they return to an operator at the end of their shop.
The operator then prints out the invoice ready for payment.
"This new process has two great advantages for our customers," said Booker stores director Andrew Muldoon.
"They see the running total of how much they have spent and also speed up the check-out process."
"So far, self-scan has significantly improved speed of service and has been well received by customers across all three branches," he added. "We will continue to monitor this and gather more customer feedback before deciding any future plans."