Cheapest UK supermarket revealed ahead of Christmas - and it knocks Lidl off the top spot

Aldi has reclaimed its position as the UK's most affordable supermarket, edging out rival Lidl by just over a pound in November's price comparison.

The German-owned discounter topped the latest Which? analysis with a 70-item shopping basket averaging £121.22 throughout the month.

Lidl, which held the crown in October, came in at £122.35 for customers using its Lidl Plus loyalty scheme, or £122.40 for those without membership.

The consumer group's monthly research examines prices across eight major grocery chains, tracking both branded products and own-label goods including staples such as milk, bread and butter, alongside popular items like Birds Eye peas and Hovis loaves.

Special offers and loyalty discounts are factored into the calculations, though multibuys are excluded from the analysis.

Among the larger supermarket chains, Asda emerged as the best value option, with the same 70 items totalling £133.59.

Tesco shoppers using a Clubcard paid £133.65 on average, saving £2.55 compared to the £136.20 charged to non-members.

At Sainsbury's, Nectar cardholders spent £137.77, while those without the loyalty card faced a bill of £141.62 for identical products.

Morrisons sat in the middle at £137.40, with Ocado charging £154.37.

For households requiring a broader selection, Which? also tracks a larger basket of 183 items excluding the discounters due to their more limited branded ranges.

Asda topped this comparison at £455.52, nearly £10 cheaper than Tesco's Clubcard price of £465.23.

Sainsbury's Nectar members paid £471.84, while Morrisons loyalty customers spent £476.96.

Waitrose occupied the most expensive position across both measures, with the premium retailer charging £166.79 for the smaller 70-item basket

This represents a difference of more than £45 compared to Aldi, meaning families choosing the budget chain over Waitrose would keep a substantial sum in their pockets.

The gap widens considerably for larger shops, with Waitrose's 183-item total reaching £522.91.

That figure stands £67.39 higher than Asda's equivalent basket, highlighting the significant premium attached to shopping at the upmarket grocer.

When comparing the extremes, Waitrose's smaller basket costs 38 per cent more than the same items purchased at Aldi.

Asda has pledged to reduce prices further as it seeks to recover market share lost to discount competitors in recent years.

Reena Sewraz, Which? retail editor, said: "While Aldi is the cheapest supermarket this month, the discounters battling it out each month means shopping at Lidl is also a great money-saving option, according to our latest price analysis."

She added: "The longer list of groceries shows that Asda continues to be one of the UK's cheapest supermarkets and a good option for those who want to choose from a larger range of branded goods."

With the festive season now weeks away, grocery costs remain a pressing concern for many British households.

The Which? findings demonstrate that simply selecting one retailer over another could reduce shopping bills by as much as 27 per cent.

An Asda spokesperson responded to the research by stating the chain continues investing in lower prices to shield customers from inflation, describing itself as the UK's cheapest full-range supermarket.