Which? has once again named Aldi the cheapest supermarket in its monthly price comparison, beating Lidl by just over £2. The consumer champion analysed the prices of 95 grocery items across eight major supermarkets throughout May 2026, using an independent price comparison website.
Price Breakdown for May 2026
At Aldi, the average cost of the shopping basket was £168.30, marginally cheaper than Lidl, where the same items cost £170.58 with a Lidl Plus loyalty card, or £170.66 without. Asda took fourth place at £192.58, followed by Tesco with a Clubcard at £196.88, Morrisons at £197.50, and Sainsbury’s with a Nectar card at £198.79.
Shoppers without loyalty cards paid more: Tesco without Clubcard was £202.27, and Sainsbury’s without Nectar was £206.18. Waitrose was the most expensive at £235.49 – that’s 40% more than Aldi, or a difference of £67.19. However, the premium retailer recently announced a £20 million price-cut initiative on everyday staples. Ocado was the second most expensive at £217.86.
How Which? Conducts Its Analysis
Which? checks prices of hundreds of grocery items at eight major supermarkets throughout the year, using an independent price comparison website. For each supermarket, the consumer champion calculates the average price of each item across the month, then sums them to get each store’s average price.
The list of 95 items includes both branded and own-brand products, such as Cathedral City, Birds Eye, and Hovis. The analysis incorporates special offer prices and loyalty prices where applicable, but not multibuys. Which? never shares the full list of products with retailers.
Reena Sewraz, Which? Retail Editor, commented: “Many people are still struggling to keep up with the cost of living and while juggling loyalty apps or chasing short-term promotions can sometimes pay off, shoppers just want reliably low prices with no strings attached. Our research shows that Aldi and Lidl completely dominate when it comes to everyday value, so it’s no surprise that they are thriving as people permanently change how they shop. When choosing the wrong supermarket can mean paying up to 40% more for comparable essentials, you can make massive savings just by switching where you do your weekly shop.”
Cheapest Supermarkets May 2026
- Aldi – £168.30
- Lidl (including Lidl Plus) – £170.58
- Lidl – £170.66
- Asda – £192.58
- Tesco (including Clubcard) – £196.88
- Morrisons – £197.50
- Sainsbury's (including Nectar) – £198.79
- Tesco – £202.27
- Sainsbury's – £206.18
- Ocado – £217.86
- Waitrose – £235.49
