Royal Mail has warned customers that they only have 100 days left before stamps without barcodes are phased out.
The postal service has said it is 'reinventing' the stamp for the next generation, which will be rolled out from January 31, 2023.
The new system will feature barcodes that allow 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.
What are the new stamps and why are they changing?
These new stamps will be similar to the regular stamp featuring the profile of the Queen but will have an added barcode on the right-hand side.
Royal Mail has said that the barcodes are part of a modernisation drive that will enable new services.
When will stamps become invalid?
All non-barcoded stamps will be valid for use until January 31, 2023.
After this date, non-barcoded stamps will be treated as insufficient postage.
If not used they can be swapped for the new stamps using a swap-out form available online. They cannot be swapped in-store. Royal Mail is yet to confirm an end date for when the older stamps can be swapped.
The new stamps are not connected to the change of monarch following the Queen's death.
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.
How to swap your old stamps
Royal Mail is offering a swap system to help with the change.
To “Swap Out” simply fill in a form from the Royal Mail website and send the old stamps via freepost to the postal service.
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