New research shows that supposedly 'bargain' items on sale in Poundland can be as much as 50% more expensive than those in other supermarkets.
Last week Poundland announced sales in excess of £1bn for the first time which makes them Europe's largest single-price discount retailer, the Daily Mail reports.
The latest research shows that groceries such as milk and cornflakes are more expensive in the bargain superstores in comparison to supermarkets such as Waitrose and Sainsbury's.
A 250g box of Kellogg's Cornflakes would set you back £1 in Poundland, but you can buy a 750g box in Waitrose and Tesco for just £1.98, the Telegraph reports.
This means that the price per unit was 52 per cent higher at the bargain store than it was at Waitrose.
A 105g bag of Galaxy Minstrels can be bought in Poundland for £1 but a bigger, 153g bag can be found in Asda for just 98p.
A six-pack of Tunnock's tea cakes costs just 81p at Waitrose but is sold at £1 per pack in Poundland.
Poundland's spokesman said: "We conduct price surveys every two weeks against the supermarkets and we believe we are 40 per cent cheaper or more against 1,000 branded products.
"Comparing either supermarket promotions or larger pack sizes with our prices is not a meaningful comparison.
Poundland hit the headlines again recently with reports of its supposed £55m acquisitions of the 99p Store chain.
According to the Guardian, Poundland would have to sell as many as 80 of their stores to gain approval from The Competition and Markets Authority (CMA) for the takeover.
But, the deal was thrown into doubt last week and Poundland face a full competition investigation from the CMA.