MARTIN Lewis has warned shoppers over a huge change to Tesco Clubcards - which leaves you with just hours to cash in.
The MoneySavingExpert.com (MSE) founder said Brits must act now to get the best deals.
Speaking on the first episode of the new series of his Martin Lewis Money Show, he said Tesco is cutting the value of points spent with reward partners from midnight on Thursday June 15.
Tesco extended the deadline from midnight on Tuesday.
The extension means you have until midnight tomorrow night to exchange and triple the value of your points at various reward partners including Pizza Express and Zizzi.
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From Friday, Clubcard vouchers will only be worth double their value if exchanged at any of Tesco's 100 reward partners.
The move will mean that their value won't go as far as it used to on things like family days out at Alton Towers Resort, meals at PizzaExpress, sunny getaways with Hotels.com and much more.
Speaking on the Martin Lewis Money Show last night, he said: "Currently you can get three times the value of your [points with] Tesco Clubcard Rewards partners.
"It's been that way for years.
"Now from Friday it's dropping permanently to two times. So a fiver becomes a tenner. That's all.
"So swap now, you can do it online."
He urged shoppers to go online, check your points value and swap as soon as possible to get the best savings.
It comes after dozens of Tesco shoppers this week complained they couldn't redeem their vouchers.
One shopper said: "I’ve managed to get two lots of Cineworld vouchers over the last week but still have nearly £180 worth of points to claim (that's it tripled)."
Without the extension if they were unable to redeem them, the shopper would have missed out on £60 worth of rewards.
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Other angry shoppers were left fuming after the website crashed for them, and they had called on Tesco to extend the deadline.
Tesco told shoppers it was experiencing "very high volumes" of customers exchanging their Clubcard vouchers for reward partner codes, and there could be delays in processing orders.
The retailer's website was also beset with issues on Monday night, according to DownDetector, which measures outages, as shoppers rushed to convert points.
Responding to complaints on Twitter at the time, the supermarket giant confirmed "there has been a few IT issues today".
It's not the first time Tesco has suffered issues with its website or app.
In May, shoppers were left fuming after being stuck with huge bills following a Clubcard glitch.
How does Tesco's Clubcard work?
Through the Tesco Clubcard, customers earn points when shopping which can then be turned into vouchers for money off food or other partner schemes.
You get one point for every £1 spent in store and online and after scanning your app or card.
Until tomorrow, you also get one point for every £2 spent on fuel.
Every point you accrue is worth 1p, so 150 points gets you £1.50, at which points you can request a voucher.
You can then use these vouchers for money off your next shop or at one of Tesco's reward partners.
The way you redeem your points with partners varies depending on which one you are redeeming with.
For example, you can use £12 worth of points to get a three-month LES MILLS+ membership worth £36.
You just have to go on the Tesco website, add the bundle to your basket and then look out for a confirmation email.
A second email containing your Reward Partner code will arrive shortly after which you can then use to activate your three or 12-month membership.
