https://www.delcampe.net/en_GB/collectables/store/stampmall

StampMall is now on Delcampe

https://www.gbos.org.uk/index.php/Home

GB Overprints Society (GBOS) helps members and collectors to explore the many ways in which,

and reasons why, British stamps and other postal material have been overprinted,
whether it is for use outside the UK or for special functions within the UK.

https://www.zirinskystamps.com/

Zirinsky Stamps specializes in stamps revenues (including railway and parcel stamps),

cinderellas and postal history from Australia, New Zealand,

the Pacific (including US and French Territories), the Caribbean, Africa,

other British Empire/ Commonwealth Countries as well as German Colonies.+++

https://punkphilatelist.com/

Postage Stamps are Pop Culture

Stampboards.com

STAMPBOARDS - Postage Stamp Chat Board and Stamp Forum

Stampboards – The World’s No#1 Bulletin Board to discuss STAMP COLLECTING and PHILATELY!!

http://www.norphil.co.uk/

We try to be the web's number 1 resource for up-to-date news

 about new stamps of Great Britain.

https://thedigitalphilatelist.com/

The Digital Philatelist

 For Modern Stamp Collectors

https://adminware.ca/machin/

Are you a Machin Nut like I am? Then enjoy the over 3,000 varieties
identified here for collectors of the Great Britain Machins...

Also some really good Machin Album Pages

stampnewsaustralasia.com.au

The Southern Hemisphere’s Only Stamp Monthly

https://www.stampworld.com/en/

The most complete stamp
catalogue in the world...

https://www.museumofphilately.com/

The Museum of Philately becomes a Non-Profit Organisation

and appoints Simon Martin-Redman as its new President

https://www.mbp-circle.co.uk/

The Modern British Philatelic Circle brings together collectors of Great Britain stamps and related items issued during the reigns of Queen Elizabeth II and King Charles III. It offers something for everyone, regardless of level of experience or years of collecting.

https://chrisdehaer.blogspot.com/

Blog covering modern Australian stamps. Information on new issues, reprints, postal stationery, exhibitions, most of which is unavailable elsewhere.