As of April 2010, the .UK domain extension is the fourth most popular top-level domain worldwide, after .com, .de and .net. However, it is prohibited to register a domain name directly under .UK (ie. domain.uk) and a second-level domain (ie. domain.co.uk) must be used.

The .co.uk domain is the most commonly used second-level domain used for the .UK extension, followed by .org.uk.

There are two ways to register your .co.uk (or .org.uk) domain name:

1. direct with Nominet (the governing authority of the .UK domain extension)
2. via a Nominet Member (ie. Doteasy.com)

The registration fees for a .co.uk or a .org.uk domain name cover a period of two years (regardless of where you registered the domain). This means your registration payment gives usage rights over the domain name for 2 years. A renewal fee is payable for each subsequent 2-year period.