Aldi was the cheapest supermarket in the UK in October, with an average household basket full of groceries and other essentials coming in at £75.79.
The same basket would cost shoppers £77.68 at Lidl, according to consumer group Which?, while Asda’s basket came in at £84.98.
Waitrose was the most expensive supermarket — with a basket of 48 general items coming to £101.17, making it £25.38 more expensive compared to Aldi.
Reena Sewraz, Which? money expert, said: “Food prices everywhere have surged lately but, month after month, our research shows there is money to be saved on the basics if you can get to one of the cheaper supermarkets.
“Shopping around, checking grocery prices per unit, and writing a list of what you need beforehand are good ways to help you budget.
Read more: Iceland to offer 1p ready meals this week
“Supermarkets have a crucial role to play in helping their customers navigate the tough months ahead so it’s important budget ranges are widely available and pricing is clear.”
In a wider analysis of 148 items across the six "traditional" supermarkets Asda was the cheapest supermarket at £348.38.
The next cheapest was Sainsbury's at £355.65, around £7 more. Waitrose was £44.56 more expensive than Asda, coming in at £392.94, on average, for the same trolley of goods.
Aldi and Lidl were not included in the larger shop comparison, as many brands can’t be found at the discounters. This larger trolley of goods included items such as Andrex toilet paper and Cathedral City cheese.
Fraser McKevitt, head of retail and consumer insight at Which?, said: “The cost of living crisis is still hitting people hard at the checkouts and this latest data will make tough reading for many.
“Based on our numbers, the average household is facing a £643 jump in their annual grocery bill to £5,265 if they continue to buy the same items. Taking that at a basket level, that’s an extra £3.04 on top of the cost of the average shopping trip last year which was £21.89.”
Sales of supermarket own-label wonky veg were up by 38% for the period, and overall own-label sales increased by 8.1%.
Julie Ashfield, managing director of buying at Aldi, said: “As we get closer to Christmas, families across the nation will be looking for ways to cut costs.
“This can be a challenging period for many in the best of years, but never more so than right now, which is why we remain committed to supporting our customers in every way we can.
“We strive to provide the highest quality products at the best possible price and we’re thrilled that this dedication has been recognised yet again by Which?”
Aldi has been named the cheapest supermarket in the UK for the fifth month running.