.citadel
.citadel is a brand extension, run by Citadel Domain LLC since 2016. Only Citadel Domain LLC, its affiliates and trademark licensees can register .citadel names; they are not for sale to the public.
| Type | Brand |
|---|---|
| Registry operator | Citadel Domain LLC |
| Who can register | Brand owner only Brand extension: only the registry operator, its affiliates and trademark licensees register names. |
| In the root zone since | 23 July 2016 |
| DNSSEC | Signed |
| RDAP server | https://rdap.identitydigital.services/rdap/ |
| WHOIS server | whois.nic.citadel |
| IANA record | iana.org/domains/root/db/citadel |
Look up a .citadel domain
The .citadel registry publishes registration data over RDAP. The free domain report reads it and shows a .citadel domain's registrar, dates, status and DNS in one place. For the raw record, use the WHOIS lookup.
New to extensions? The guide to how domain extensions work covers generic, country-code and brand extensions. For who sells extensions in general, see the list of domain registrars.
Sources: the IANA root zone database and the ICANN list of generic extensions (refreshed 2026-10-24). Something out of date? Tell us.
Frequently asked questions
Who runs the .citadel extension?
Citadel Domain LLC is the registry operator for .citadel. The registry keeps the list of every .citadel name; registrars sell the names to the public.
Can anyone register a .citadel domain?
Only Citadel Domain LLC, its affiliates and trademark licensees can register .citadel names; they are not for sale to the public.
When was .citadel created?
.citadel was added to the DNS root zone on 23 July 2016, according to IANA.
How do I look up who owns a .citadel domain?
The .citadel registry publishes registration data over RDAP at https://rdap.identitydigital.services/rdap/ and over WHOIS at whois.nic.citadel. The free domain report on lemon.domains reads it for you and shows the registrar, dates and status.
Is .citadel signed with DNSSEC?
Yes. The .citadel zone is signed, so a .citadel domain can turn on DNSSEC once its registrar adds a DS record.