The process of transferring a .UK domain name from another Registrar is slightly different compared to the process for domain names under other extensions. In case of a .UK domain name, the Transfer In needs to be initiated at the Current Registrar's end.
As per the Transfer process, a mail is sent by the system to the Registrant Contact email address once the Transfer has been processed successfully by the .UK Registry. This email will be sent with your Registrar Branding details.
In case the Registrant does not receive this email or has misplaced it, it can be resent from within your Registrar/Reseller Control Panel, by following the below mentioned process:
Login to your Control Panel. See details
In the Menu, point to Products -> Domain Registration and click .UK Transfer-In Notifications.
Select the check box adjacent to the domain name's Security Key, for which you wish to resend the notification.
Click the Resend Mail button on the bottom of the page.