On 10th June 2014, the new .UK TLD officially launches and becomes available for anyone to register.
We have already added support for .UK registrations to WHMCS and so in order to begin taking orders for this new TLD in WHMCS, you will just need to do two things:
1. Add the TLD along with your desired pricing in Setup > Domain Pricing
2. Add a new WHOIS Server Definition to the default WHOIS Servers list shipped with WHMCS. To do this, you need to open the /includes/whoisservers.php file with
Read more @ http://blog.whmcs.com/?t=89631