Britain's biggest supermarket also offers the most reliable email service, it has been claimed.
Email delivery statistics for the UK's top broadband providers have been compiled by tech research firm Epitiro.
In analysis which covered the 12 months to March 2008, Tesco's broadband service was found to have the highest rate of successful delivery, posting 99.9 per cent within three minutes of the mail being dispatched, ISPreview.co.uk reports.
Virgin Media came second on 99.8 per cent, with Orange and Pipex the two other broadband providers who broke 99 per cent. In fifth place was Demon, which delivered 96.3 per cent within the time limit.
Epitiro's study also identified the email "rush hour" as 5-6pm on Tuesday, when heavy usage made it comparatively less likely to successfully send a message. An estimated seven per cent of emails despatched in this hour are either markedly delayed or lost altogether.
Gavin Johns, marketing director at the firm, commented: "If you think email is 100 per cent reliable, think again. Consumers and businesses seeking a reliable email service need to consider performance metrics when choosing a service provider, and certainly shouldn’t choose an ISP on price alone."
He added: "What’s more, IT managers should set email performance standards with their chosen ISP before the service begins."
