Stamps are soon to undergo a pretty major change. (Picture: Getty Images)

A major change is coming in for stamps in the UK – and no, we don’t just mean the Queen’s portrait being replaced by that of King Charles and his cipher.

A new scheme is being introduced to digitalise stamps, and it means many people’s old stamps will no longer be valid.

But, before you despair over your mountain of First Class books, there is a way to exchange them.

Find out when the old stamps will expire and how to swap them out…

When do stamps expire?

Traditional stamps will no longer be valid from January 31, 2023.

After this date, regular stamps without the new digital barcode cannot be used.

No barcode, no valid stamp – don’t post anything important! (Picture: Mike Kemp/In Pictures via Getty Images)

The stamps that will need changing are the stamps many will be familiar with – it’s any stamp which features a profile of the late Queen Elizabeth against a plain coloured background.

That is to say, any stamp which doesn’t also include a scannable barcode.

The barcodes are being added to stamps moving forward to enable new digital services.

The only stamps you don’t need to exchange are special issue stamps – these are often commemorative or include artwork of a famous person or place, like the recent Iron Maiden release. These will remain valid without a barcode.

How to exchange your old stamps

Your non-barcoded stamps can be exchanged for the new barcoded version through the Stamp Swap Out scheme.

To swap out your stamps, simply complete a Stamp Swap Out form and send it to Royal Mail along with your non-barcoded stamps.

If you have a printer, you can swap out up to £200 worth of non-barcoded stamps by printing out and completing this Stamp Swap Out form.

The new stamps will have a scannable barcode (Picture: Royal Mail)

You can send this back to us free of charge, along with your stamps, by writing on the envelope Freepost SWAP OUT – No other address details or postcode are needed.

If you have a printer and more than £200 worth of stamps to swap out, then use the Bulk Stamp Swap Out form.

This must be sent to:

Royal Mail, Swap Out, Tallents House, 21 South Gyle Crescent, Edinburgh, EH12 9PB.

If you don’t have access to a printer, you can request a Stamp Swap Out form to be posted to you by completing this form.

Stamp Swap Out forms are also available from the Customer Service Point at your local Delivery Offices.

Will stamps of the Queen still be valid if they have a barcode?

Another question you may be asking is, even with the barcodes, will stamps with the Queen be valid once King Charles’ stamps come into circulation?

The answer is – yes. Eventually, only stamps with Charles’ portrait will be sold, so stamps of the late Queen will fall out of circulation naturally.

But until that point over the next few years, it’s inevitable we will see two monarchs on our post, with both QEII and KCIII stamps in use, something which has not been seen for many years.

This use of stamps is known as ‘mixed franking’ or in this case ‘mixed reigns’, and has previously occurred for the stamps of Edward VII and George V during 1911-13, George V and George VI during 1937-39, and George VI and Elizabeth II between 1952 and 1955.

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