Exclusive research conducted by NationalWorld has revealed almost 200 items have been affected and between 2 May and 6 June, price rises of up to 100% were recorded for 175 products across Tesco, Asda, Sainsbury's, Morrisons and Aldi.
The prices of almost 700 basic range products across the aforementioned five supermarkets were tracked as part of the research, which has involved taking an online price snapshot on the first Monday of each month.
Speaking on NationalWorld's Uncovered podcast, the national director of charity Feeding Britain Andrew Forsey insisted people were being 'clobbered' by the rising prices of basic essentials.
He said: “Life is an enormous struggle for all too many people who are being clobbered by those price rises in basic essentials.
“What we see at Feeding Britain is that often when pressures are being applied to household budgets, food is the first item to be sacrificed because no one kicks you out or sends you to jail if you don’t buy food whereas they could do if you don’t pay the rent or the bills.”
Asda raised the prices of 46 of the 157 value range products tracked by NationalWorld, making just 12 price decreases during the tracking period. Of the 46 products that had their prices raised, 10 had seen price rises for two consecutive months.
The supermarket is currently rolling out their Just Essentials range to replace their Smart Price line. 28 product replacements were recorded between 2 May and 6 June, and eight of the Just Essentials products were more expensive than the Smart Price ones they replaced. Just four were cheaper.
An Asda spokesperson told NationalWorld: “We know that many customers are finding things tough at the moment and we are focussed on keeping prices down for them.
“Despite rising inflation in the market, we have either reduced or held prices on 113 of the products featured in this survey.”
229 items from Tesco were tracked, 51 of which have been the subject of a price rise since May.
18 of the items tracked went up in price for two consecutive months, meanwhile just six price decreases were recorded.
A spokesperson for Tesco told NationalWorld: “With household budgets under increasing pressure we are absolutely committed to helping our customers, by keeping a laser focus on the cost of the weekly shop.
"We have significantly increased the number of value lines we offer and whether it’s price matching basics to Aldi prices, promising Low Everyday Prices on household staples, or offering exclusive deals and rewards through thousands of Clubcard Prices – we’re more committed than ever to providing our customers with great value.”
Of the 137 Sainsbury's items tracked, just one went down in price. 38 had their price raised and four were raised for two consecutive months.
A spokesperson from Sainsbury's told NationalWorld: “We know that customers are counting every penny right now and we are relentlessly focused on keeping prices low – especially on the products that our customers buy most often such as meat, fish, poultry, dairy and fresh produce.
“While prices can go both up and down for a variety of reasons, our targeted campaigns such as our Sainsbury’s Quality, Aldi Price Match and Price Lock promise give customers reassurance they don’t need to go anywhere else to get the best deals.”
47% of the 43 Morrison's products tracked had their price raised between May and June, although several returned to the price they had during the previous month following a price cut.
Their Savers range has also been expanded and 100 products will now be tracked by NationalWorld.
A Morrisons spokesperson told NationalWorld: "We are doing everything we can to keep all of our prices as low as we can for our customers. Due to current global pressures on our food supply chains, the cost of 12 of these Savers products has gone up within the last three months – similar to increases we have also seen in our mid and top tier product ranges."
Aldi has a reputation for low prices but NationalWorld observed 20 price increases whilst tracking 93 items. Five products had their cost lowered.
An Aldi spokesperson told NationalWorld: “We are the lowest priced supermarket in Britain and our customers always pay less for their shop with Aldi, which is why we were named 2021 Cheapest Supermarket of the Year by consumer champion Which?.
“Value is the number one consideration for most households as they wrestle with rising costs and our promise to our customers is that we will always provide the lowest grocery.”