Royal Mail has issued a 100-day warning to customers as it phases out stamps without a barcode.

Customers have been warned that their ‘1st’ and 2nd’ class stamps will be unusable from January 31 2023 as Royal Mail introduces a new system.

The "reinvented" stamps feature a barcode which will you to watch videos, messages, and much more information all available on the Royal Mail App. 

Themed, commemorative and non-barcoded Christmas stamps will still be usable after the deadline and will remain unaffected by the change.

Isle of Wight County Press: PAPA (Image: PA)

Royal Mail urges customers to use their 1st and 2nd class stamps before deadline

Royal Mail has said that the barcode will also help to introduce "added security features" and "pave the way for innovative services for our customers".

It added that the barcode will also help to introduce "added security features" and "pave the way for innovative services for our customers".

If you can't use the older stamps by the January 31 deadline, you will be able to exchange them for newer barcoded ones free of charge.

Royal Mail is yet to confirm an end date for when the older stamps can be swapped.

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Its advice is not connected to the change of monarch following the passing of Queen Elizabeth II in September.

Further details on the launch of stamps featuring King Charles III  are expected to be made at the appropriate time after consultation with the Royal Household, the Royal Mail has said.

Royal Mail announces stamp swap ahead of new barcode system

Royal Mail is offering a swap system to help with the change.

The “Swap Out” scheme will be running from 31 March 2022 to 31 March 2023.

To “Swap Out” simply fill in a form from on the Royal Mail website. The page is not yet live however Royal Mail has moved to assure people that it will be soon.