Data last verified: 3 October 2026. Figures re-checked against their primary sources under the Whito rolling re-verification programme.
Finding
On 3 October 2026, 36 answers from ChatGPT, Gemini and Google AI Mode in 12 UK cities said 20 times that a named firm was Gas Safe registered, and gave a registration number twice.
Source: Whito, whito.co.uk/gas-engineers/research/ai-gas-engineer-recommendations-gas-safe, 2026-10-03. Free to quote with a link to this page.
Last Updated on October 5, 2026
Collected: 3 October 2026. 36 AI answers: ChatGPT, Gemini and Google AI Mode, asked the same question in 12 UK cities. Registration claims checked against the Gas Safe Register by registration number the same day.
Gas work is the one trade where the law is simple. Anyone working on gas in your home must be on the Gas Safe Register. So when an AI engine recommends a gas engineer and calls them “Gas Safe registered”, that is a claim you can check, and should.
On 3 October 2026 we asked ChatGPT, Gemini and Google AI Mode “Recommend a trustworthy gas engineer in [city]” in 12 UK cities. The 36 answers named 140 firms. 20 times, an answer said a named firm was Gas Safe registered. A registration number came with that claim twice. Where we could find a number and check it, the register agreed: 5 of 5 were Registered. For the rest, the answer gave you a claim and no way to check it.
What we found
- Every answer mentioned Gas Safe. All 36 used the words. Fewer pointed to the register itself: 11 of 36 linked to gassaferegister.co.uk.
- 20 claims that a named firm is registered. Gemini made 12 of them, ChatGPT 5 and Google AI Mode 3. A registration number came with 2 of the 20.
- The claims came from the wrong places. ChatGPT sourced three of its claims to directories, MyBuilder and Yell, and two to the firm’s own website. None was sourced to the register.
- Nothing we checked was wrong. We confirmed 5 claimed firms on the register by number. None was contradicted. Two more firms print a number we could not check, because the register’s site stopped us with a security check.
- “Gas Safe” is also a trading name. Businesses with the words “Gas Safe” in their names were recommended in 4 of the 36 answers. The words alone tell you nothing about registration.
Engine by engine
| Engine | Answers | Firms named | Linked the Gas Safe Register | Said a named firm is registered | Told you to check |
|---|---|---|---|---|---|
| Google AI Mode | 12 | 52 | 7 of 12 | 3 | 12 of 12 |
| ChatGPT | 12 | 57 | 2 of 12 | 5 | 12 of 12 |
| Gemini | 12 | 31 | 2 of 12 | 12 | 4 of 12 |
| All | 36 | 140 | 11 of 36 | 20 | 28 of 36 |
“Told you to check” means the answer advised checking the register or asking to see the engineer’s Gas Safe ID card. The two habits pull in opposite directions. Google AI Mode and ChatGPT told the reader to check every time and made few firm-level claims. Gemini made most of the firm-level claims and told the reader to check in 4 answers out of 12.
What we could check, and what we could not
The Gas Safe Register can be searched by name or by registration number. Name searches set off a human verification check on 26 September 2026, which Whito does not complete. Searching by number worked. So we looked for a Gas Safe number on each claimed firm’s own website, read as plain text, and checked every number we found.
| Outcome for the 20 claims | Count |
|---|---|
| Number found and confirmed Registered on the register | 5 |
| Number printed on the firm’s site, register check stopped by a security check | 2 |
| No number found in the text of the firm’s site (a number may be in an image) | 9 |
| Firm’s own site not found, did not load, or a national network | 3 |
| Claim not tied to one named firm | 1 |
| Contradicted by the register | 0 |
Two of the five confirmed numbers came straight from the AI answer. Three we found on the firm’s own site. That is the useful lesson: the firms that print their number make the claim checkable in under a minute. The rest ask you to take it on trust.
A company record is not a gas registration
One recommended firm shows why both checks matter. Its old limited company was dissolved in 2018, according to Companies House. The Gas Safe number on its website was Registered on the Gas Safe Register on 3 October 2026, under the business’s trading name. A check of Companies House alone would have marked it a fail. A dissolved company is a register fact, not an allegation, and here it said nothing about the gas registration.
Against our September check
On 26 September 2026 we asked the same engines for a trustworthy plumber, and 0 of 24 answers linked the Gas Safe Register, with 5 claims that a named firm was registered. See the plumber register check. Asking for a gas engineer by name brought the register into the answer far more often. The prompts differ, so read this as a contrast, not a trend.
If you are booking a gas engineer
Treat “Gas Safe registered” in an AI answer as a claim, not a check. Ask the engineer for their Gas Safe ID card when they arrive, and check the card number or the business’s registration number on the Gas Safe Register. The back of the card shows which kinds of gas work the engineer is qualified for, so check it covers your job.
If you are a gas engineer
This is Start stage work and it costs nothing. Print your Gas Safe registration number on your own website as plain text, not only inside the logo image. AI engines repeat what they can read. Of the firms an AI answer said were registered, the ones that printed a number were the only ones a customer could confirm in a minute. Not sure what an AI engine can read on your site? The free Visibility Check takes about twenty seconds and needs no email.
What this does not prove
- We checked registration claims, not workmanship. A Registered result says the business was on the register on 3 October 2026, nothing more.
- No number found in the text of a site does not mean a firm is not registered. Many show their number inside an image, which our text search cannot read.
- We did not search the register by name, so we have not checked the firms that no answer called registered.
- “Trustworthy” is the wording of our prompt, not our verdict on any firm.
- One run per prompt, on one day, in a signed-in UK browser. Answers change from day to day and between accounts.
How we did it
On 3 October 2026 we asked each engine “Recommend a trustworthy gas engineer in [city]” for Leeds, Manchester, Birmingham, Bristol, Sheffield, Nottingham, Leicester, Coventry, Newcastle, Cardiff, Southampton and Brighton. ChatGPT was used in a temporary chat with web search, Gemini in the free app on its default model, and Google AI Mode in a UK browser. We recorded every firm named, every statement that a named firm was Gas Safe registered, the source the answer gave for it, and whether the answer linked the register. Google AI Mode stopped answering for part of the day: in five cities the first attempt produced no answer, so we asked once more later and counted that answer. ChatGPT lost one answer to a technical fault before we could record it, and we asked once more. The file says which. For each registration claim we searched the firm’s own website for a Gas Safe number in its page text, then checked each number on the Gas Safe Register’s public Check service and recorded the outcome only.
The data behind this page
The file holds every answer, every firm named, the exact wording of each registration claim, its stated source, the number found on the firm’s site and the register outcome with its date. Ask for it through Whito Data and we will quote a fixed price in writing. Nobody can pay to be added to a study, removed from one or moved within one. How Whito makes money.
Cite this research
Whito Research (2026). We asked AI for a trustworthy gas engineer. Then we checked the Gas Safe Register. On 3 October 2026, 36 AI answers in 12 UK cities said 20 times that a named firm was Gas Safe registered, and gave a registration number twice. https://whito.co.uk/gas-engineers/research/ai-gas-engineer-recommendations-gas-safe/. Free to quote with a link.
Corrections and right of reply
If your business is named in this research and you think we have a fact wrong, email hello@whito.co.uk. We check it against the register, correct it within five working days if we are wrong, and publish your statement alongside if you want us to. Full route: corrections, right of reply and removals.
Questions
Can I trust an AI answer that says a gas engineer is Gas Safe registered?
Treat it as a claim to check. On 3 October 2026, 36 answers from ChatGPT, Gemini and Google AI Mode in 12 UK cities said 20 times that a named firm was Gas Safe registered, and gave a registration number only twice. Every claim we could check by number was correct.
Do AI answers link to the Gas Safe Register?
Sometimes. 11 of 36 answers linked to gassaferegister.co.uk on 3 October 2026: Google AI Mode 7 of 12, ChatGPT 2 of 12 and Gemini 2 of 12.
How do I check a gas engineer is registered?
Ask to see their Gas Safe ID card and check the card number or the business registration number on gassaferegister.co.uk. The back of the card lists the gas work they are qualified to do.
Is a business called Gas Safe registered with the Gas Safe Register?
Not necessarily. The words can appear in a trading name. Businesses with “Gas Safe” in their names were recommended in 4 of 36 AI answers on 3 October 2026. Check the registration number, not the name.
If your business is named here and you think we have a fact wrong, email hello@whito.co.uk and we will check it and correct it. If you want to respond, send us a statement and we will publish it alongside. Full detail: Corrections, right of reply and removals.
