A savvy way to unlock a supermarket trolley without a £1 coin has been revealed.

There's lots of things to remember when heading out to one of the big chains for the weekly shop, including a shopping list and carrier bags, but many often forget to check if they have a £1 coin in their purse or wallet for the trolley.

As the use of cash declines while contactless payments rises, shoppers who forget to bring a coin for the trolley are faced with having to cram everything into a small basket.

What is the shopping hack to get a trolley without a pound coin?

The tip was shared by one clever customer on a popular Facebook group.

"If you don't have a pound coin or a trolley coin put 2 20s [20p's] together and boom it will work," the shopper posted.

The so-called shopping 'hack' should apply for trollies at supermarkets including Asda, Aldi, Tesco, Sainsbury's and Morrisons.

Which supermarkets are the cheapest and most expensive?

Consumer watchdog Which? analysed the prices of 78 essential items at the UK’s biggest supermarkets to determine which offered the best value in the month of June 2020.

The report factored in the costs of staple shopping items, including both branded and non-branded lines.

Own brand products including pasta, olive oil, milk and salad tomatoes, were among those that were price checked, as well as branded items such as Hovis wholemeal bread.

Findings revealed that Lidl offered the best value for money, costing the average customer £72.02 for all 78 goods.

The supermarket - which uses the tagline “Big on quality, Lidl on price” - proved to be the cheapest place for customers to shop for groceries and household items throughout June.

Aldi came in at a close second, with the shop costing just 21p more, at a total of £72.23.

This was followed by Asda, where shopping would set customers back £80.15.

Which supermarket is the most expensive?

On the other end of the scale, Waitrose was found to cost customers almost £40 more.

The same 78 products cost the average customer £11.77 at Waitrose, making it the most expensive of the UK’s main supermarkets.

How did all the supermarkets rank?

Here’s how the six major UK supermarkets ranked in terms of price for a 78 item shop, listed from the cheapest to the most expensive:

  • Lidl - £72.02
  • Aldi - £72.23
  • Asda - £80.15
  • Tesco - £88.28
  • Morrisons - £90.27
  • Sainsbury’s - £93.93
  • Ocado - £109.61
  • Waitrose - £111.77