Keep an eye on https://www.royalmail.com/prices2024 - there, they’ll have the postage rate leaflets to download
Current rates, hopefully valid at least until the end of the year (Royal Mail need to give 30? days notice). Bah humbug, 2nd price rise announced.
From 2nd October 2023:
1st - £1.25, large £1.95
2nd - 75p, large £1.55
Surface mail / International Economy, 100g to outside Europe, £2.00
Airmail / International Standard, 100g postcards/letters, £2.20
Postage rates from 2nd April 2024.
1st - £1.35, large £2.10
2nd - 85p, large £1.55
Surface mail / International Economy, 100g to outside Europe, £2.20
Airmail / International Standard, 100g postcards/letters, £2.50
There is a minimum size for international mail. “One surface must be at least 9cm x 14cm” found on their get a price site.
Also keep an eye on Postcrossing’s Postal Monitor, and service updates from Royal Mail:
International - https://personal.help.royalmail.com/app/answers/detail/a_id/5317
UK - https://personal.help.royalmail.com/app/answers/detail/a_id/12556
Adding a couple of blogs covering stamp news from the UK, and from the Commonwealth (and former Commonwealth).
https://blog.norphil.co.uk/ Norvic Philatelics.
https://commonwealthstampsopinion.blogspot.com/ Commonwealth Stamps Opinion blog.