Money Saving Expert Martin Lewis has urged everyone to buy a cheap 50p Tesco item by the end of November.
The TV man and money guru Martin says you can use the '50p trick' with your Clubcard to get £9.50-worth of vouchers back.
He announced the tip on the ITV Martin Lewis Money Show.
This comes after a revelation that £13m-worth of Clubcard vouchers are set to expire at the end of November.
Speaking on the ITV Martin Lewis Money show, he said: "When you got them two years ago, they only last two years and there's a deadline and people still haven't used £13M of them.
"So check whether you've got them at Tesco.com/Clubcard or via its app.
"But here's the trick: if you've got them and you don't want to spend them now.
"Take your £10 voucher, go online and buy a 50p restaurant voucher on its rewards page, which is worth £1.50.
"Now, you will get reissued £9.50, the change, in vouchers and they are new vouchers so they have a two-year lifespan.
"So that's a way to extend them." Speaking of deadlines, Martin Lewis also told viewers that the deadline to use up old stamps - the ones which don't have the barcode on them - has been extended.
Previously they were due to expire in January but now the deadline has been extended to July 31.
And Martin also urged shoppers of all major supermarkets - so Waitrose, Asda, Sainsbury's and Morrisons as well as Tesco - that there are a few 'free food' deals available to redeem at supermarkets while stocks last.
This includes Onken Kefir yoghurt at £1.65 at Waitrose, redeemable via Shopmium app, a 2L Coke Zero at £2, whereby you can buy it at Morrisons and then upload your receipt at Hashting to get the money back, a Pieminster gravy, at £4, available via Hashting through Waitrose in the same way, and a VFC Chick*n (ie meat free) tender at £3 you can buy at Sainsbury's and claim back with code FREEVFC when shopping online at Sainsbury's.
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