registry: definition

A registry is the central database of a top-level domain (TLD), such as .com or .es, together with the systems that run it. Every name registered in that TLD is recorded there. People also use the word for the organization in charge, although the precise name for that organization is the registry operator.

What a registry is

ICANN Internet Corporation for Assigned Names and Numbers The nonprofit that coordinates the global DNS and gTLD policy. Full definition of ICANN describes a registry as the authoritative master database of the domain names registered in a TLD. Each TLD has one registry. ICANN’s Registry Agreement The contract between ICANN and a gTLD registry operator. Full definition of Registry Agreement lists the core registry services:

receiving registration data The information kept about a domain and its owner. Full definition of registration data from registrars;
running the TLD’s name server A server that holds a domain's DNS records and answers lookups. Full definition of name server;
publishing the zone file, which the DNS uses to find the name servers for each name in the TLD;
publishing contact and other registration data.

When someone visits example.com, the DNS consults the .com registry to find which name servers answer for that name.

As of October 2026, IANA Internet Assigned Numbers Authority The functions that coordinate the root zone, IP addresses and protocol numbers. Full definition of IANA lists VeriSign Global Registry Services for .com and Red.es The Spanish public body that manages the .es domain through its unit Dominios.es. Full definition of Red.es for .es. Spain’s Orden ITC/1542/2005 makes Red.es the authority that manages the registry of .es names.

Registry operator versus back-end provider

The registry operator holds the right to run a TLD and sets its rules: who may register, on what terms and at what wholesale price What a registry charges a registrar for each domain name. Full definition of wholesale price. For a gTLD generic top-level domain A top-level domain not tied to a country, run under ICANN contracts. Full definition of gTLD, that right comes from a Registry Agreement with ICANN, which under the base agreement runs for ten years and renews for further ten-year periods unless it ends. For a ccTLD country code top-level domain A top-level domain for a country or territory, usually two letters long. Full definition of ccTLD, it comes from a local framework, such as the 2005 order for .es.

Many operators hire a back-end provider A company that runs a TLD's technical systems for the registry operator. Full definition of back-end provider to run the technical systems. ICANN calls it a Back-End Registry Operator or Registry Service Provider (RSP). ICANN treats five functions as critical:

DNS resolution for registered names;
the SRS Shared Registration System The registry system that all registrars connect to in order to manage domains in a TLD. Full definition of SRS, the system registrars use to create and manage names;
the RDDS Registration Data Directory Services ICANN's umbrella name for public lookup services for registration data, formerly WHOIS and now RDAP. Full definition of RDDS, the registration data lookup services such as RDAP Registration Data Access Protocol The modern protocol for looking up domain registration data, replacing WHOIS. Full definition of RDAP;
data escrow Backup copies of registration data held by an independent agent in case a registry or registrar fails. Full definition of data escrow deposits;
a zone properly signed with DNSSEC Domain Name System Security Extensions Digital signatures that prove DNS answers are genuine and unchanged. Full definition of DNSSEC.

Hiring a provider does not move the responsibility: under the base agreement, the operator stays bound by all its obligations. applicant An organization that has applied to ICANN to run a new gTLD. Full definition of applicant in ICANN’s 2026 round of new gTLD A generic top-level domain added to the internet through ICANN's New gTLD Program. Full definition of new gTLD must name one or more RSPs evaluated through the RSP Evaluation Program Registry Service Provider Evaluation Program ICANN's one-time technical check of gTLD back-end providers. Full definition of RSP Evaluation Program.

How registrars connect to a registry

Under the base agreement, names in a gTLD must be registered through ICANN-accredited registrars, with limited exceptions. ICANN accreditation ICANN approval that allows a company to register gTLD domains as a registrar. Full definition of ICANN accreditation is not enough on its own: each registrar also signs the registry’s RRA Registry-Registrar Agreement The contract between a registry and a registrar that sells its domains. Full definition of RRA (RRA), one step of registry accreditation A registry's approval for a registrar to sell domains in its TLD. Full definition of registry accreditation. The registry must use the same agreement for all registrars and give non-discriminatory access to every accredited registrar that signs it and complies with it.

The technical link is the SRS, which registrars reach through EPP Extensible Provisioning Protocol The protocol registrars use to manage domain names at registries. Full definition of EPP, a standard protocol the base agreement requires.

The Registry Code of Conduct Contract rules that stop a gTLD registry from favoring its own registrar. Full definition of Registry Code of Conduct (Specification 9 of the agreement) bars a registry from giving any registrar preferential access unless all can qualify on similar terms. It also bars front-running: registering names based on inside knowledge of what people search for.

ccTLDs can work differently. The 2005 order for .es provides for accredited registrars competing freely, and also allows applicants to apply directly to Red.es.

How registries earn money

A registry charges registrars a wholesale price for each year of a new registration Obtaining the right to use a domain name for a set period. Full definition of registration or renewal Paying to extend a domain registration for more time. Full definition of renewal, and for each transfer between registrars. Registrars then set their own retail price What a customer pays a registrar or reseller for a domain name. Full definition of retail price. Under the base agreement, registrars must get at least 30 days’ notice of a price increase for new registrations Domains newly created in a period, also called adds or creates. Full definition of new registrations and 180 days for renewals.

legacy TLD A gTLD that existed before the 2012 New gTLD Program, such as .com. Full definition of legacy TLD such as .com have their own agreements. As of October 2026, the .com agreement (version of 1 December 2024, initial term through 30 November 2030) sets a maximum price that started at US$10.26 per year and may rise by up to 7 % a year under set conditions; a price of US$10.97 is scheduled from 1 November 2026. Verisign must charge all ICANN-accredited registrars the same price.

When a registry changes hands or providers

A sale

In a registry acquisition The sale of a TLD or its operating company to a new owner. Full definition of registry acquisition, a buyer takes control of the operator or receives the TLD itself. Under the base agreement, both a change of control and an assignment of the Registry Agreement need ICANN’s prior written consent, which may not be unreasonably withheld, and the operator must notify ICANN at least 30 days in advance. ICANN checks the buyer’s finances and operational and technical capabilities, and runs background checks.

As of October 2026, ICANN says it responds within 10 calendar days when the buyer already operates a gTLD, and within 30 when it does not. Its fees for assigning one TLD to a new operator typically do not exceed US$19,000.

A change of back-end provider

A move to a new back-end provider is what ICANN calls a Material Subcontracting Arrangement (MSA) change. The steps are an informal submission, approval of a transition plan, Registry System Testing (RST), formal submission and ICANN review, ICANN’s determination, and the move itself. A provider that either supports no gTLD yet or has not passed the 2026 evaluation also needs a technical evaluation (estimated at US$14,300 as of October 2026) and a simulation exercise. As of October 2026, ICANN advises allowing at least 7 to 12 weeks. An assignment and an registry transition Moving the operation of a TLD to a new registry operator or back-end provider. Full definition of registry transition must be done one after the other, not at once.

ICANN uses “registry transition” for a change of the party holding the Registry Agreement; in industry usage the term covers both kinds of move.

A failure

If DNS or DNSSEC is down 4 hours in total in a week, or EPP or RDAP and RDDS 24 hours in total in a week, ICANN may hand the critical functions to an EBERO Emergency Back-End Registry Operator A stand-by provider that temporarily runs a failing gTLD registry's critical functions. Full definition of EBERO (EBERO). As of October 2026, the providers are CIRA Canadian Internet Registration Authority The not-for-profit organization that runs Canada's .ca domain. Full definition of CIRA (CIRA), China Internet Network Information Center (CNNIC) and Nominet The organization that runs the .uk domain registry. Full definition of Nominet. EBERO does not apply to some legacy gTLDs. The rescue relies on data escrow, a copy of the registry data the operator deposits every day. An emergency operator normally accepts no new registrations; if no successor registry comes forward after a call for proposals, the TLD is closed.

Registry, registrar and registrant: the three roles

ICANN summarizes a registration this way: the registrant The person or organization that holds a domain name registration. Full definition of registrant registers a name with a registrar; the registrar checks that the name is available and sends the request to the registry operator; the registry operator adds the name to the registry. reseller A business that sells domains using another registrar's accreditation. Full definition of reseller offer registrations through a registrar.

The contracts follow the same chain: the registry operator signs with ICANN (Registry Agreement); the registrar signs with ICANN (RAA Registrar Accreditation Agreement The contract between ICANN and each accredited registrar. Full definition of RAA) and with each registry (RRA); the registrant signs with the registrar.

registry