Supermarket comparison basket: August's cheapest revealedAsda cheapest supermarket for our basket in August

05 September 2014

Woman searching in supermarket shelves

Sainsbury's was the second cheapest supermarket in August in our comparison

Asda was cheapest for our basket of branded supermarket goods in August, with Sainsbury's moving into second place.

Asda charged an average £177.09 for the 89 products, with Sainsbury's moving from second most expensive last month to second cheapest this month, charging £187.43 for the basket. We also compared prices from the other major online supermarkets Ocado, Tesco and Waitrose.

Our basket includes between 80 and 100 products from big brands and includes everything from bottled water to biscuits. We average the prices across the month, including special offer discounts but not multibuys. We change the contents of the basket over time so the results aren't comparable between months.

If you're a Which? member you can can log in to see how the supermarkets have ranked over the last year, on our supermarket prices compared page. If you're not already a Which? member, you can get instant access with a £1 one-month trial. In order to work out the average price of our basket we used data from the independent shopping website Mysupermarket

17.2%Asda's market share

Asda is on the rise

Asda continues to be cheapest for our comparison basket and its market share is on the rise, reaching 17.2% in the last 12 weeks, according to consumer research firm Kantar Worldpanel. Waitrose also did well making it to 4.9%.

In contrast the other three of the big four, Tesco, Sainsbury's and Morrisons felt the squeeze and Tesco issued its third profit warning for 2104 in August.

At Which? we survey over 10,000 people each year to discover how customers rate their supermarket for everything from customer service to value for money and look at both in store and online experiences. You can find out how the major supermarkets shaped up in our survey.

Supermarket price comparison schemes

Most supermarkets have a price comparison scheme, which means that if some or all of your shopping would have been cheaper at another supermarket you may be offered a voucher for the difference. 

Asda, Ocado, Sainsburys and Tesco have price comparison schemes. The supermarkets they check against, the products they include and the terms can differ. For example, Asda gives you a voucher if your shopping isn't 10% cheaper, Sainsbury's only compares branded products and Ocado only checks against Tesco.

Waitrose price matches Tesco on branded items and this is included in our monthly price comparison. 

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