Ocado has launched an SMS reminder service designed to prevent customers forgetting about their delivery and going out - which happened more than 1,000 times last year.

Customers can opt in to the service, which sends a text alert with details of the driver's name, van type and registration. It will also list items missing from the delivery. "More than two thirds of our customers work and roughly the same proportion have children so they are some of the busiest people in the country," said Ocado trading and marketing manager Jon Rudoe. "It's easy to understand why they occasionally forget that we're due to deliver."

The scheme had been tested on Ocado employees before being launched, he added.

Rudoe refused to comment on speculation Ocado was attempting to negotiate a new long-term supply contract with Waitrose. It is currently on a one-year rolling contract to source own-label and branded lines from the retailer.