Royal Mail has added special barcodes to stamps, making it possible for people to watch videos, read messages and view other information from senders.
The move, which starts on Tuesday, follows a successful trial, with the aim of connecting a letter with the digital world.
Customers can scan the barcodes while using the Royal Mail app and will eventually be able to watch videos, information about services, or even birthday messages and other greetings from senders.
At the moment, a video featuring Shaun the Sheep, created exclusively for Royal Mail by animation studio Aardman, is available to view.
It is the first in a series of planned videos to be released during 2022 that will allow customers sending stamped mail to choose which one the recipient can see when they receive an item of mail.
The new barcoded stamps will have a “digital twin” and the two will be connected by the Royal Mail app.
The barcodes match the stamp colour and sit alongside the main body of the stamp, separated by a simulated perforation line.
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The barcodes will be available on so-called “definitive” stamps – the regular, everyday stamps featuring the profile of the Queen.
Non-barcoded definitive and Christmas stamps will remain valid until January 2023.
Nick Landon, Royal Mail chief commercial officer, said: “Introducing unique barcodes on our postage stamps allows us to connect the physical letter with the digital world and opens up the possibilities for a range of new innovative services in future.”