Use Your Old Postage Stamps . . .

[Buenchico]

. . . within the next 12 months, as they'll cease to be valid after 31 January 2023.

If you're buying new ones though, enjoy watching Shaun the Sheep ;-)

https://www.royalmail.com/sending/barcoded-stamps?iid=H1_BARCODEDSTAMPS

[Mamyalynne]

If you have a stash left over then make use of the free exchange when it opens, just like happens the bank notes.

[jno]

Christmas cards mostly. But I shall be sorry to trade in all my old stamps with King Edward VII on them.

[Khandro]

I have a cache of English postage stamps (my mum's r.i.p.) which are at least 12 years old, marked simply as 1st & 2nd I use them regularly for use within the UK with no problems.

[jno]

those are I think among the ones being replaced by similar ones but with barcodes

[jno]

actually, small point, but are those barcodes or QR codes? I thought barcodes were just bars

[FoxLee2]

I collected commemorative stamps from the sixties up to 2000 when I realized I was just doing it out of habit. Sometime ago someone came to value the collection and offered me £30 which I turned down. I have since been using the stamps from the decimal ones onwards so going back 50 years. I shall have to write a lot of letters before next January to use as many as I can. Incidentally, it is legal to use stamps from the current monarch and for the previous two but since decimalisation, you would have had to use an awful lot of the old stamps to make up to 85p.