The UK’s 50 busiest online shops had website load times three-times slower than the industry standard during the first quarter of this year, so says NCC Group’s latest retail benchmark report.

Data revealed the websites had an average load time of 9.36 seconds, more than three times the recommended standard of just three seconds.

Separate research by cloud platform Akamai suggests 40 per cent of customers start to abandon websites after this amount time.

NCC said websites were getting bigger, with slower-loading sites five times ‘fuller’ than the fastest ones.

Bob Dowson, director of NCC Group’s web performance division, said: “Site owners are getting more ambitious, just as consumers are becoming more demanding.

“The list of must-have features, from social media feeds to image galleries, is growing ever longer. A large web page isn’t necessarily a slow page, but there is usually a strong correlation.”