.aco
.aco is a brand extension, run by ACO Severin Ahlmann GmbH & Co. KG since 2015. Only ACO Severin Ahlmann GmbH & Co. KG, its affiliates and trademark licensees can register .aco names; they are not for sale to the public.
| Type | Brand |
|---|---|
| Registry operator | ACO Severin Ahlmann GmbH & Co. KG |
| Who can register | Brand owner only Brand extension: only the registry operator, its affiliates and trademark licensees register names. |
| In the root zone since | 27 August 2015 |
| DNSSEC | Signed |
| RDAP server | https://rdap.nic.aco/ |
| WHOIS server | whois.nic.aco |
| IANA record | iana.org/domains/root/db/aco |
Look up a .aco domain
The .aco registry publishes registration data over RDAP. The free domain report reads it and shows a .aco 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 Something out of date?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 .aco extension?
ACO Severin Ahlmann GmbH & Co. KG is the registry operator for .aco. The registry keeps the list of every .aco name; registrars sell the names to the public.
Can anyone register a .aco domain?
Only ACO Severin Ahlmann GmbH & Co. KG, its affiliates and trademark licensees can register .aco names; they are not for sale to the public.
When was .aco created?
.aco was added to the DNS root zone on 27 August 2015, according to IANA.
How do I look up who owns a .aco domain?
The .aco registry publishes registration data over RDAP at https://rdap.nic.aco/ and over WHOIS at whois.nic.aco. The free domain report on lemon.domains reads it for you and shows the registrar, dates and status.
Is .aco signed with DNSSEC?
Yes. The .aco zone is signed, so a .aco domain can turn on DNSSEC once its registrar adds a DS record.