Tesco warns millions of shoppers to take action before 11.59pm on Thursday

A Tesco shopper warning has been issued - as triple point voucher codes are expiring this week. Tesco, which is the UK's largest supermarket chain and biggest retailer, warned last month that almost £20million Reward Partner codes are due to expire very soon.

Tesco said that there is £20million worth of codes which have been requested but not redeemed. It is urging customers to use them up before they become invalid. When Tesco announced the change last year, it said any codes redeemed before the June 13 deadline would be valid for a year, instead of six months.

That means anyone who requested the codes before this deadline has until Thursday (June 13) to redeem them. Tesco has emailed customers in May asking if they have codes that are due to expire.

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When you collect Clubcard points, you can convert them to Tesco vouchers to use at the store – for example, 500 points are usually worth £5. But if you exchange your vouchers for codes to spend with Tesco's Reward Partners, 500 points become worth £15. Partners include Hotels.com, Pizza Express, Legoland and 100s of other retailers.

Speaking last year, Tesco’s Chief Customer Officer, Alessandra Bellini, said: "We want to help customers’ household budgets stretch further right now and Clubcard unlocks the best value from Tesco - from thousands of exclusive deals through Clubcard Prices to money off your groceries and fuel, or redeeming vouchers with the biggest and most generous Reward Partner scheme.

“While we are making a change to how members can use their vouchers with our Reward Partners, we want to remind millions of Clubcard holders to redeem their vouchers at 3x the value until 13th June so they can use their Reward Partner codes to give themselves and their families a well-deserved treat. We have extended the validity of redeemed codes at the 3x rate, so if swapped before the deadline, they will be valid for a year, instead of six months, to give customers even more time to enjoy them.”