The Food Warehouse offers a Bonus Card which can be used by shoppers to allow them to save even more

A supermarket's loyalty card can slash shopping bill by up to a fifth, it has been found.

The Food Warehouse was formed in 2014 and is part of Iceland Foods. It is now one of the fastest growing supermarkets in the UK and promises to provide a 'simpler way to shop', by offering bigger pack options and therefore better value on well known brands.

The store also offers a Bonus Card which can be used by shoppers to allow them to save even more. Anyone can get a card and once it's scanned at the till, or used online, you get the Bonus Card price on selected products, rather than the usual price.

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The MEN tried using the card during a shop this week, and saved more than 20% on their shopping bill with deals and Bonus Card prices. Among the biggest savings was a whopping 640g stuffed crust Chicago Town pizza, reduced from £4 to £2.75, and two large packs of cereal for £4, saving £2.20.

With the Bonus prices, as well as savings on other offer items, it brought their total bill down from £123.17 to £101.12, a saving of £22.05, almost 22%.

There were plenty of other stand-out reductions too - like the current offer on John West Tuna Chunks, with four 145g tins reduced to £2.50 - that's even cheaper than Asda's £3 price in the retailer's 'Dropped and Locked' promotion, which has seen prices fixed until the end of the year.

Meat worked out cheaper than other places, at three packs for £9 on everything from chicken and gammon to burgers and mince - and it's the lean stuff rather than 20% fat.

And there were savings to be had on household products and toiletries too, like two bottles of Cif on multibuy for £2, an 85-wash bottle of Comfort fabric softener reduced to £3.75 and large packs of cleaning and floor wipes for £1 each.

It's not just the products that's making this place appealing to shoppers either - delivery is free if you spend £40 online and if you buy from the store but can't get it all home, perhaps you're on foot, then they'll also deliver it free providing you spend over £20.

The Bonus Card also doubles up as a savings card and for every £20 you put on it to spend there, it gives you £1 on top. This frozen retailer might be relatively new to the world of supermarkets, but it sure isn't small fry and it's easy to see why The Food Warehouse is giving other supermarkets the shivers.

Here's my full food shop from The Food Warehouse (showing promotions and Bonus Card prices)

Total £123.17 / with Bonus Card and offers 101.12