The code that matches — and isn't used
The United Kingdom's ISO 3166-1 code is GB, so by the usual rule its ccTLD should be .gb. But the UK had already been using .uk since 1985. .gb exists in the root zone, yet it has never been opened for registrations, and IANA's record shows it as reserved. Every British website you know lives under .uk instead.
Watch out for
- Not open for registration
.gb by the numbers
.gb is the internet country code for United Kingdom. It's one of Northern Europe's ccTLDs, the two-letter domains reserved for countries and territories.
A little context on United Kingdom: the capital is London, the main language is English, the currency is the British pound (GBP) and the international dialing code is +44.
United Kingdom shares land borders with 1 country, so the ccTLDs next door are .ie (Ireland).
IANA lists Reserved Domain - IANA as the manager of .gb. ccTLD managers set their own policies — who can register, which second-level names exist, pricing to registrars — so those rules differ from country to country.
On the technical side, .gb is served by 3 authoritative name servers, 2 of them reachable over IPv6. There is no DS record for .gb in the root zone, which means the TLD is not DNSSEC-signed at the top level.
United Kingdom also has another country-code domain in the root zone: .uk.
.gb FAQ
Can I register a .gb domain?
No. .gb is in the root zone but is reserved and has never been opened for registration.
Why does the UK use .uk instead of .gb?
.uk was already established in the early DNS. "UK" is exceptionally reserved in ISO 3166-1 so it can coexist with the official "GB" code.
What country is .gb?
.gb is the country-code top-level domain for United Kingdom, in Northern Europe.
What is United Kingdom's domain extension?
United Kingdom's website extension is .gb, its country-code top-level domain. It also has .uk in other scripts. "GB" is its ISO 3166-1 alpha-2 code.
Who owns the .gb domain?
IANA lists Reserved Domain - IANA as the manager of .gb: it runs the registry and sets the rules for United Kingdom's ccTLD. Individual .gb names belong to whoever registers them.
Is .gb DNSSEC-signed?
No. As of our last data refresh there is no DS record for .gb in the root zone.
Sources
Data from IANA root zone version 2026102000. Last changed October 21, 2026. Spotted something wrong? Tell us.
