Sainsbury’s won The Grocer 33 awards for service and availability this week for the fifth consecutive year - with service levels improving still further - but the most improved retailer is Waitrose, according to annual analysis of our mystery shopper data.

In the 51-week nationwide competition, Waitrose scored 69.5 out of 100 on average for its weekly mystery shops - up from 63.9 last year.

The increase saw Waitrose overtake Morrisons to secure third place in the annual ranking, behind leader Sainsbury’s score of 73.8 and Tesco’s 70.9 (up 2.3ppts and 2.6ppts respectively).

Waitrose improved on every single metric, including its checkout score, which increased by 1.5 points on last year to 13.5 out of 20, while the average time spent queueing and scanning items also decreased (though queuing and scanning times are now shortest at Tesco).

The improvement comes after Waitrose set out plans to focus on its existing estate rather than continuing its aggressive expansion strategy, which has seen branches increase from 146 in 1999 to 352 today.

The three-year estate revamp, which began last year, will see all stores undergo improvement work ranging from full makeovers to simple upgrades in lighting, service counters and flooring by 2019.

waitrose haywards heath

Waitrose Haywards Heath 

Waitrose ploughed 25% of its profits into improving stores in 2016-17, and this year will increase that figure to 40%.

Most recently, its work has included introducing self-service tills into more branches.

Wim van Aalst was also brought in as its new supply chain director last August, with a brief to improve some of its antiquated systems and processes.

Waitrose retail director Ben Stimson said: “We are always looking to improve our customers’ shopping experience so it’s encouraging this has been reflected in the scores we received as well as a number of our branches winning ‘store of the week’ recently.”

Clive Black, analyst at Shore Capital, said the improvement in Waitrose’s Grocer 33 score reflected a “strategic evolution” among the management team.

“They don’t have the same growth coming from new store space so they are putting that effort into store standards,” he said.

“I think it’s rare we ever say Waitrose stores look bad but the Waitrose stores I’ve been around in recent months have been in good shape.”

IGD pointed out the restructuring of Waitrose branch teams - phasing out the role of department manager to create “more flexible” teams - could also have boosted the service score. “This is boosting the productivity of each store, as well as service levels,” said Nick Gladding, senior retail analyst at IGD.

Asda’s average service levels fell to a new low of 63.3, but availability improved 1.3ppts.