General
- Extension
- .co.uk
- Type
- Second-level extension
- Meaning
- Second-level zone under .uk (United Kingdom)
- Parent extension
- .uk
- Registry
- Nominet UK
- Registry website
- www.nic.uk
- Registered since
- 24 July 1985 (.uk)
Properties
- DNSSEC in the root zone
- .uk: yes
- Name servers
- .uk: 8 (8 with IPv6)
- WHOIS server
- -
- RDAP server
- rdap.nominet.uk/uk
- At 1blu
- available to order directly
Registration conditions
- Who may register?
- Anyone, with no status check. .co.uk is intended for commercial purposes.
- Allocation
- In order of application (first come, first served).
- Length
- The full name including the extension has at most 64 characters.
- Characters
- a–z, 0–9 and hyphen, no hyphen at the beginning or end. No IDN names.
- Registrant data
- Correct name, postal address, phone and e-mail. Requests from Nominet to confirm or correct the data must be answered promptly; with false or outdated details the domain may be cancelled or suspended.
- Transfer
- Currently without an auth code: the current registrar or the registrant (via Nominet's online services) moves the domain to the new registrar's TAG. From 9 February 2027 a Transfer Authorisation Code applies, which the current registrar must provide free of charge within 5 days.
- New rules
- From 9 February 2027, Nominet's new UK Registration Policy applies.
- Blocked names
- Names such as ac, co, gov, ltd, me, net, nhs, org, plc or sch cannot be registered under .co.uk.
Sources: Nominet: Rules of registration (20 March 2024) · Nominet: UK Registration Policy 2026-03 (from 9 February 2027) · Nominet: Terms and conditions · Nominet: Consultation on the transfer process · Nominet: Transfer policy from 9 Feb 2027 · IANA Root Zone Database: .uk · As of 28 October 2026