Sainsbury’s shoppers are paying almost £1,467 more for 52 weekly shops than Aldi customers, even if they have a Nectar card, according to new research.

Aldi narrowly beat discount rival Lidl to hold on to its crown as the cheapest UK supermarket in the last month, according to Consumer group Which? 

But Sainsbury’s shoppers using the supermarket’s loyalty card Nectar would still pay on average £214.04 a week compared to Aldi’s £185.83 basket. It means Sainsbury’s shoppers face paying £1,466.92 more over the course of 52 weekly shops than Aldi shoppers for an equivalent basket of goods, if the same price difference average was maintained over a year.

Without a Nectar card, the same items at Sainsbury’s cost £223.84.

The consumer champion’s monthly analysis involved comparing the average price of a shop consisting of popular groceries at eight of the UK’s biggest supermarkets. 

Discounter Lidl was close behind Aldi in January, costing only 76p more with the supermarket’s loyalty scheme Lidl Plus and 79p more without, £186.59 versus £186.62 on average.

When it carried out a larger shop Which? found that Asda was the cheapest supermarket. It came out the cheapest £518.90, beating Tesco shoppers who used a Clubcard by £10.11, or £529.01.

The larger shop did not include Aldi and Lidl because it did not include the comparable items.

Last month Asda dropped its Aldi and Lidl price match scheme. Instead it brought back Rollback pricing – claiming to have slashed the prices of more than 4,000 products in-store and online by an average of 25%.

Waitrose was the most expensive on average, with a bigger shop costing £592.34. 

The list of 100 items included both branded and own-brand items, such as Birds Eye Peas, Hovis bread, milk and butter.

The analysis includes special offer prices and loyalty prices where applicable, but not multibuys.

For the smaller shop, Tesco Clubcard members would have paid £207.66 on average – while without a Clubcard, the Tesco shop cost £213.14. 

Reena Sewraz, retail editor at Which?, said its research found Asda has made up some ground after slipping back in its rankings in recent months.

“With people still feeling the effects of food inflation, they are likely looking to cut costs where they can. Our analysis shows that by switching supermarkets consumers could save up to 23%, highlighting the advantages of shopping around where possible.”