After bucking the promotional trend last month, Sainsbury’s has fallen back in with the pack slashing the number of deals it ran in the four weeks to 22 May by 10.6%.

But it is one of only two retailers whose activity is up year-on-year. The retailer has increased its promotions 6.1% more than twice the rate of the only other retailer to up activity, Asda. It has also overtaken the other supermarkets to offer the biggest average typical saving £2.16 nudging narrowly ahead of Tesco.

“Sainsbury’s is really pushing its Feed Your Family for £50 campaign and that’s one of the reasons why it has outstripped the others year-on-year in spending,” said Assosia MD Kay Staniland.

Surprisingly, it was Waitrose that swam against the flow, increasing its activity 9.2%, although it was marginally down year-on-year. “It is having to work much harder on promotion because of the competition,” said Staniland. “It is still working out its promotional strategy and the increasing spend is a sign it’s realising how important it is.”

Asda was the only chain other than Sainsbury’s to boost its year-on-year activity. But it seems to be making good on its long-term pledge to slash promotions as its deals were down 12.5% month on month. The only retailer to cut back more was Tesco, which ran 17.4% fewer promotions.

There has also been a discernible shift by some retailers towards own-label promotions. A year ago, Asda ran more than four times as many promotions on brands as on own-label goods, but in the month leading up to 22 May this changed to a ratio of 71:29. Sainsbury’s, meanwhile, has moved from 80:20 to 68: 32 and also offered the biggest average percentage savings on own-label products, at 31.88%.

There has been a major uplift in own-label activity supporting ranges such as Asda’s Chosen by You, said Staniland, but it would not necessarily be long term. “It all depends on whether they have something to shout about,” she said.

Retailers adopted different promotional tactics from each other over the Easter and Royal Wedding period especially when it came to beers, wines and spirits. At Tesco and Waitrose, activity was up more than in any other category month-on-month, but Asda’s was only up marginally and Morrisons’ and Sainsbury’s were down.

Overall, fruit accounted for 13.17% of activity, more than twice the share it had a year ago. Activity was down on categories such as ambient confectionery and cakes & pastries.