The European Commission will revoke all of the .eu domain name registrations owned by UK citizens post-Brexit. Although at the time of writing, it is clear that no one can predict with certainty when that might be (if at all) but, as it stands, the legal framework for the .eu Top Level Domains allows only the EU undertakings, EU organisations or EU residents to register .eu domain names.
On 28 March 2018, the European Commission issued a notice regarding the .eu domain names registered by UK residents which confirmed that "subject to any transitional arrangement that may be contained in a possible withdrawal agreement, the EU regulatory framework for the .eu Top Level Domain will no longer apply to the United Kingdom as from the withdrawal date. […]".
“As of the withdrawal date, undertakings and organisations that are established in the United Kingdom but not in the EU and natural persons who reside in the United Kingdom will no longer be eligible to register .eu domain names or, if they are .eu registrants, to renew .eu domain names registered before the withdrawal date. Accredited .eu Registrars will not be entitled to process any request for the registration of or for renewing registrations of .eu domain names by those undertakings, organisations and persons.”
On 10 April 2018, the EURid, the .eu registry, received a notice from the European Commission stating: “The revocation of existing holders’ rights and the prohibition for registrars from processing any more requests for registrations or renewals for .eu domain names whose holders are no longer eligible must be prepared so that the necessary measures are effective as from 1 January 2021 or, in case that there were no withdrawal agreement in force before 30 March 2019, as from 30 March 2019.”
As the draft withdrawal agreement is silent on the .eu domains (and all involved are understandably focusing on a broader issue, such as the Irish backstop), it would seem that the revocation process will take place whether or not the UK leaves with or without a deal!
UK-based owners of potentially affected domains will be notified of their non-compliance shortly before Brexit and will be given a two-month period following Brexit to remedy the situation. If at the end of that period the .eu domain is still registered to a UK-based person or entity, it will be “withdrawn”. Websites and emails associated with such domains will cease to operate. The domains’ functionalities may be recovered by their owners if EU residency criteria can be established before the first anniversary of Brexit, after which the domain registration will be fully “revoked” and the domain will become available to general registration by any compliant third party.
The simplest solution to keeping your .eu domain name registration in case Britain does leave the EU (unless you want to take your bet on it!) is to either transfer it to an EU-subsidiary outside of the UK or set up an alternative top-level domain (e.g. .com, .co.uk, .net or .org) and put in place a website migration and traffic re-direct plan as soon as possible. Even though the re-direct will no longer be possible after .eu domain is revoked, setting up a re-direct now should allow the search engines to notice it and mitigate the impact on your search engine optimisation (SEO) efforts.