EURid confirmed the policy, which has been set following discussions with the European Commission, in a Brexit notice on its website.
Businesses that fail to take action risk having their rights to use '.eu' domain names withdrawn and eventually cancelled, EURid said.
The policy announcement backs up a warning issued by the UK government late last year. That warning noted the fact that the right to register web addresses rooted in the '.eu' domain is restricted under EU law. Registration is only open to undertakings that have their registered office, central administration or principal place of business within the EU, organisations that are established within the EU, where national law permits, and natural persons resident within the EU.
EURid said: "As of 30 May 2019, 00:00:00 CEST, all registrants who did not demonstrate their eligibility will be deemed ineligible and their domain names will be withdrawn. A withdrawn domain name no longer functions, as the domain name is removed from the zone file and can no longer support any active services (such as websites or email) but the record will remain in the .eu registry database, and may be reactivated if the eligibility criteria are satisfied."
"Twelve months after the UK withdrawal, i.e. on 30 March 2020 00:00:00 CET, all the affected domain names will be revoked, and will become available for general registration. For security and stability reasons, the release of all affected domain names will occur in batches from the time they become available," it said.
EURid also confirmed that UK-based owners of '.eu' domain names will not be able to renew their '.eu' domain names if they expire after Brexit.