Tesco Clubcard vouchers worth over £15 million expire this month – here's how to triple their value (though you'll need to act soon)

Below we explain what you need to know. For more on getting the most out of Tesco's loyalty scheme, see our Clubcard reclaim and boost guide.

How to check if your Clubcard vouchers are due to expire

Clubcard vouchers are only valid for two years. If you're unsure when yours expire, and you've still got them in paper format, check the date on the voucher itself.

If you've lost your vouchers, or are unsure if you have any in the first place, you can check on the Tesco Clubcard site or app. Here's how:

• To check on the website... go to the Tesco Clubcard website, select 'Clubcard account' and then 'Vouchers'. You'll need to be registered for a Tesco.com account and must know your Clubcard number, which is printed on Clubcards and Clubcard key fobs. You should then be able to see a table listing your available vouchers and their expiry dates.

• To check on the app... open it up (if you don't have it, you can download it for free through the Apple App Store or Google Play Store), then go to 'Clubcard' and then to the 'Vouchers' section.

Once you've found your vouchers, you can spend them online using the code provided – or if you plan to spend them in store, you can print your vouchers or scan the barcode available on the app at the checkout.

If you're spending them, triple the value of your vouchers – while you still can

If you've expiring vouchers, now's a good time to spend them as currently, you can triple their value by redeeming them at Tesco's 'Reward Partners', such as Pizza Express, Legoland and others.

For example, 500 points are usually worth £5 to spend at Tesco – but if you exchange your vouchers for codes to spend with a Reward Partner, 500 points become £15.

But from 14 June, you'll only be able to double the value of your vouchers – so 500 points will only be worth £10 with a Reward Partner. This deadline only applies to swapping vouchers for reward codes; once you've made the swap, you have 12 months to use the code with your chosen Reward Partner. See our Tesco triple value rewards axed story for more about the change.

For full info on how to boost your vouchers' value, including our top partner picks, see our guide to boosting your Clubcard points to max their value.

If you don't want to spend them, use this trick to extend your Clubcard vouchers

While Clubcard vouchers are valid for two years, if yours are expiring but you don't want to use them yet, there's a crafty way you can extend the expiry date for another two years, but you must do so before 11.59pm on Wednesday 31 May. Here's how it works:

• Make a small purchase on the Tesco Clubcard Rewards page (not in store or on other Tesco pages) and the remaining balance is credited back to your Clubcard account as points.

• They'll then be reissued as new vouchers (with an expiry date up to two years in the future) when you next get a batch. So if you spend 50p using a £10 Clubcard voucher, you'll get £9.50 back as new vouchers.

• There's no minimum spend, but the aim's to shell out as little as possible. A good option might be a 50p restaurant voucher (worth £1.50 at your chosen restaurant if you swap before 14 June).

Note that you'll need to do this for each individual voucher though, so weigh up if it's actually worth it for smaller denominations. For example, if you've a £10 voucher it's probably worth it – if you've got a handful of £1 vouchers, maybe less so.