.UK WHOIS and WHOIS2 retire February 9, 2027: prepare your lookup tools
Nominet has scheduled the closure of .UK port 43 WHOIS and WHOIS2 for February 9, 2027. If your scripts, website or monitoring tools depend on either service, test their RDAP replacement before the deadline.
Update details
- Change
- Service retirement scheduled
- Scheduled retirement
- February 9, 2027
- Affected services
.UK port 43 WHOIS, .UK WHOIS2
Nominet’s service directory states that .UK port 43 WHOIS and WHOIS2 will cease on February 9, 2027, alongside its wider registry transition. It directs users of both legacy services to RDAP, the Registration Data Access Protocol.
RDAP is already available for .UK. The deadline concerns retiring the older services, not launching their replacement. Nominet lists Searchable WHOIS separately, so this announcement should not be read as a blanket closure of every service with WHOIS in its name.
Who needs to act?
Review your integrations if you maintain:
- scripts that query .UK WHOIS;
- websites that offer lookups through a WHOIS or WHOIS2 gateway;
- monitoring, security or investigation tools that parse WHOIS text; or
- third-party components that perform those lookups on your behalf.
Simply owning a .UK domain does not require you to migrate a lookup integration. The work falls to whoever operates the tools that retrieve registration data.
For example, a scheduled script might query WHOIS for a domain’s registrar and nameservers, then extract values from labeled text lines. That script can work today and stop returning useful information when the underlying service closes. A website can have the same hidden dependency even if its lookup form needs no visible redesign.
Check scheduled jobs, libraries and vendor integrations as well as your own application code.
Replace the lookup, not just the connection
RDAP returns structured JSON over HTTPS instead of WHOIS text. A practical migration has four parts:
- Discover the authoritative service. Use the IANA DNS bootstrap registry to find the current base URL for
.uk. - Request the domain record. Append
domain/and the full domain name to that base URL, preserving its existing path. - Map the fields your application uses. Select entities by role and events by action rather than relying on text labels or array positions.
- Handle incomplete results and failures separately. Missing data, an authoritative negative response, rate limiting and a network failure are different outcomes.
Nominet’s RDAP documentation recommends IANA bootstrap discovery as the mechanism for learning about endpoint changes. Our WHOIS-to-RDAP migration guide covers the implementation and rollout process in detail.
A tested .UK lookup
At verification on October 16, 2026 (UTC), the IANA DNS bootstrap file mapped .uk to https://rdap.nominet.uk/uk/. This request returned HTTP 200 with an application/rdap+json response:
curl --header 'Accept: application/rdap+json' \
'https://rdap.nominet.uk/uk/domain/nominet.uk'The response identified the object as a domain, with ldhName set to nominet.uk. Its events included registration and last-change dates, but no expiration event. That is a useful migration test: a successful lookup does not guarantee that every field expected by your old parser will be present.
Treat this URL as a verified example, not a permanent substitute for discovery. For the JSON structure and field meanings, see How to Read a Domain RDAP Response.
WHOIS2 users need to review their gateway architecture
WHOIS2 let an authorized registrar pass a website visitor’s IP address through its lookup gateway. Nominet could then apply lookup quotas to the visitor’s address rather than treating every request as coming from the registrar’s server.
In its WHOIS2 replacement guidance, Nominet says websites must trigger RDAP queries directly from the visitor’s browser rather than centralizing those checks. That preserves the visitor’s source IP for rate limiting without WHOIS2’s pass-through mechanism.
This is Nominet’s service guidance for replacing WHOIS2, not a universal requirement that every RDAP application run in a browser. For affected websites, however, simply replacing a server-side WHOIS request with a server-side HTTPS request would miss that guidance.
Test requests from your website’s origin, including cross-origin access and failure handling. A successful terminal request does not prove that browser JavaScript can read the response. Our browser troubleshooting guide explains that distinction.
Registration lookups are not availability checks
Nominet treats these as separate migrations in its registry transition instructions:
- Port 43 WHOIS and WHOIS2: move registration-data lookups to RDAP.
- Legacy Domain Availability Checker: move to EPP checks and supporting reports.
Its availability guidance explicitly says RDAP is not intended as a domain-availability service. For registrar integrations, EPP domain:check is the primary live mechanism, with drop lists and unavailable-name reports supporting other workflows.
Do not turn an RDAP 404 into an assurance that a domain can be registered. Registration availability also depends on registry policy, including reservations and eligibility rules.
Preparation checklist
- Find dependencies on .UK WHOIS and WHOIS2, including third-party tools.
- Test RDAP field mappings, missing values and error handling.
- Test direct browser access where Nominet’s WHOIS2 replacement guidance applies.
- Review polling, caching, retries and rate-limit behavior.
- Remove .UK fallback paths that assume WHOIS will remain available after retirement.
- Keep registration lookups separate from availability checks.
- Recheck Nominet’s published deadline and service guidance before deployment.
Identify and test affected integrations before February 9, 2027, rather than discovering the dependency when the legacy service closes.