Sainsbury is phasing in an “e-voucher” system for online customers who use its Sainsbury’s to You service.

Senior manager for online marketing Penny Slatter said customers would be able to tap in a voucher number when paying online, for an instant reduction on the bill. She said: “Customers will know what the final charge is, rather than waiting for a refund after handing a paper voucher to the delivery driver.”

Codes will be printed on a spectrum of vouchers from “free delivery” to money-off vouchers which can be redeemed in store as well as online.

The quicker turnaround of “thousands of vouchers a week” will allow Sainsbury to monitor promotions instantly, Slatter said.

She added that the next step would be to automate the redemption of Nectar points on the website.

“We are talking to Nectar at the moment.”