The cheapest supermarket to shop at during September 2020 has been revealed.

Alertr, an online price tracking website, which monitors the price increases and decreases across seven major UK supermarkets have published the latest data for last month.

The results have been determined by carefully tracking how each online retailer prices the 43 items outlined in the Government’s Consumer Price Index ‘shopping basket’ on a week-by-week basis.

What did the price tracking website find out from the supermarkets during September 2020?

Asda was cheapest for three out of the five weeks, with Iceland taking the top spot for the last two weeks of September.

However, even with Iceland’s average basket cost being £2.09 cheaper than last month, Asda still took the overall crown despite the average total being up 0.20p on its August pricing.

At the other side of the spectrum, Tesco was crowned the most expensive supermarket for the month of September, but has now been knocked down a peg or two by Ocado which comes in with an average basket spend of £151.24, £3.31 more than last month and £11.60 more than Tesco.

Ocado was sold out of the same or like for like pasta in week’s one and two, but this didn’t affect the pricing as it was still the most expensive across all of the seven retailers.

Beers (such as San Miguel Premium Lager 440ml) saw the most consistent price fluctuations across retailers, week one it was priced at £5.50 in Asda, but by week three the price had dropped to £4.60.

What have researchers found?

Andy Barr, co-founder of, said: “It is interesting to see that, once again, Waitrose has unexpectedly been more affordable than some of our go-to ‘cheaper’ stores that one may assume they are going to find more reasonably priced items within.

"Despite Tesco continuously coming up as one of the more expensive retailers, the data from September does seem to indicate that they’ve begun to drop their prices as we enter another tricky phase regarding the global pandemic.

“Sainsburys is also another surprise as it comes in third cheapest retailer for the shopping list, somewhat surprising as it’s notoriously known for its higher-end offerings.

"At this point, it’s starting to look like Asda can’t be beaten on their low prices, and competitors will really have to think about introducing better deals or offers in order to keep customers loyal, particularly at a time when so many are looking to cut their spending in any way possible.”

Who are Alertr?

Online price tracking website Alertr ( has been tracking the prices of 43 everyday items from the shopping basket on the Office for National Statistics’ Consumer Price Index (CPI) since 2019.

Included within the list are items such as eggs, milk and bread, as well as non-perishables like pasta, rice and cereal.

Own-brand items (or their equivalent) were monitored in the research to give the most unbiased comparison of goods and their prices, with the exception of brands that all seven supermarkets stocked (e.g. Coca-Cola).

Why aren't Aldi and Lidl included?

The prices across seven of the largest supermarkets are analysed, with discount retailers Lidl and Aldi not included due to the inability for customers to shop full ranges online.

The full breakdown of supermarkets average basket costs from lowest to highest over the five-week period in September 2020 were as follows:

  1. ASDA - £130.36 – 20p more than last month      
  2. Iceland – £132.40 - £2.09 less than last month     
  3. Sainsburys - £135.24 - £4.27 less than last month
  4. Waitrose - £139.50 – 64p more than last month
  5. Tesco - £139.64 - £9.34 more than last month
  6. Morrisons - £141.53 - £4.22 less than last month   
  7. Ocado - £151.24 - £3.31 more than last month    

What item had the most price fluctuations in September?

According to Alertr, Teabags (Yorkshire Tea 750g) at Morrisons stayed the same price every week, until week five when they went from £5 to £7, this type of price rise is common and we will likely see it drop back to £5 in a few weeks to make consumers think they are saving money.