Tesco shoppers will from today get money off instantly if their grocery bills would have been cheaper at Asda, Morrisons or Sainsbury's.

Previously the supermarket ran a 'Price Promise' where it gave you a voucher if your branded, own label and fresh food groceries were cheaper at rivals Asda, Morrisons or Sainsbury's.

The difference with its new 'Brand Guarantee' is that now, rather than issuing vouchers, the difference automatically comes off your total bill at the till or online, though Tesco's done away with its own label comparison, with the new scheme only comparing branded goods.

Tesco says the new scheme "removes the hassle and inconvenience of price match vouchers" – it's now the only supermarket to automatically deduct savings – while similar schemes run by other major supermarkets all issue vouchers to redeem instead.

The move follows a successful trial in Northern Ireland over the last few weeks, and also comes after Morrisons announced it's axing its price match scheme, which gave shoppers the difference back if their shop was cheaper at Aldi, Asda, Lidl, Sainsbury's and Tesco (see the Morrisons shoppers dealt blow MSE news story for more on this).

Our Q&A below explains how Tesco's new scheme works (also see our Supermarket Shopping Tips guide for tricks to slash your food bills).

What is Tesco's new 'Brand Guarantee'?

Tesco's 'Brand Guarantee' sees shoppers get money off if their comparable shopping bills would have been cheaper at Asda, Morrisons or Sainsbury's. However, it only applies to branded goods.

Tesco says it collects this price data from its competitors using an "independent external agency", which includes a daily web scan of Asda's and Sainsbury's grocery shopping websites and twice-weekly in-store price-checks in three Morrisons stores.

Any discount shoppers get is based on the total cost of the comparable branded items only.

Where will Tesco's Brand Guarantee work?

Tesco's Brand Guarantee is available in-store at Tesco superstores and its Metro and Extra branches. It's also available on Tesco's online grocery store.

The price match will not work in Express stores, on Tesco Direct, which sells technology, toys and household items, in petrol stations, on Tesco Wine By The Case (its wine retail arm), on Tesco Clothing (both in-store and online), in Tesco Bank and in its phone shop.

What products does the Brand Guarantee compare?

The scheme is valid on comparable branded grocery items only, such as Cadbury or Coca Cola. It also includes branded health and beauty items such as Head and Shoulders shampoo.

It excludes loose fresh food such as bakery goods, fruit and vegetables, as well as meat and fish from the deli counter, electricals, own-label goods such as the Tesco value range, cigarettes, baby formula and more – see the full list of exclusions in Tesco's T&Cs.

How does Tesco determine what a 'comparable' item is?

Tesco will only compare 'comparable items'. It determines these as being an identical item in size, colour, variant and flavour. For example, a six-can pack of Diet-Coke is not comparable with an eight-can pack of Diet-Coke.

Will Tesco price match against competitors' promotions?

Tesco says it will price match against certain promotions on the date customers do their shopping in-store or the date the shopping's delivered if you buy online. This includes matching against multibuys such as BOGOF, 3for2 and buy 2 for £x amount, and price cuts, for example if an item's usually 99p but it's been reduced to 50p.

However, it won't price match store-specific offers, clearance goods, meal deals, category-wide promos such as 'buy six bottles of wine and get 5% off', money off discounts such as a £5 off £40 shop, or coupons/vouchers and products that give you extra free, such as 50% extra free.

Tesco launches instant price match guarantee
Tesco launches instant price match guarantee

Is there a minimum spend?

No, there's no minimum spend, although you need to buy at least 10 different products, one of which must be comparable.

How do I get the money?

If you shop in-store, including on self-service check-outs, the difference will automatically be deducted from your bill before you pay and the amount will be detailed on your bill.

If you shop online at Tesco, you pay once the goods have been delivered, rather than when you place the order. So here, any deduction is made before the money is taken and you'll be able to see this on your delivery note. But to see a detailed breakdown of the savings, you can visit the Brand Guarantee website for up to 28 days from the date the receipt was issued.

Tesco says that on the "rare occasion" it might experience a technical error and can't immediately deduct the difference, it'll give you a voucher for the difference, which you can use on your next Tesco shop.

Is there a maximum amount that can be taken off my bill?

Yes, the maximum you'll get off your bill is £20 per shop.

Will Tesco Clubcard points be given on the original total, or the total after the price match has reduced the bill?

Tesco says Clubcard points will be given on the original amount, before any deductions are made. So if your bill came to £16 and you notched £4 of Brand Guarantee discounts, you'd qualify for 16 Clubcard points.

Will Tesco brand match Aldi or Lidl?

No. It's just price matching against Asda, Morrisons and Sainsbury's.

How can I max the savings?

When you're shopping, separate out branded products that seem like a particularly good bargain and those that are full price (you can put some in the front and some in the back of the trolley, or even use separate baskets). When you get to the checkout, pay for the two piles of shopping separately.

With luck, you'll have a basket packed with full price items, which will hopefully earn you a big saving off your bill, and a separate basket full of mega-bargains (which won't drag your average spend/saving on branded products down). See our Supermarket Shopping Tips for tools and tricks to slash your food bills.