How to Check a Gas Safe Engineer Before Work Starts
To check gas safe engineer credentials properly, you need the engineer's Gas Safe ID card and the official Gas Safe Register. Anyone carrying out gas work must be on the register, and the back of the card lists the specific gas work they are qualified to do. Confirm the name and photo match the person in front of you, and make sure the job is covered before work starts.
Key takeaways
- Anyone carrying out gas work must be on the Gas Safe Register, so a registration check is not optional for boilers, cookers, gas fires or pipework.
- Read the Gas Safe ID card on both sides, because the back lists the types of gas work the engineer is qualified to do.
- Search the register online yourself rather than relying on a card photo, certificate or link the engineer sends you.
- Match the registered work categories to your job, since a registration for one type of appliance does not cover every task.
- Ask for a written record of the work, and keep it with your property papers.
- If you smell gas, call the National Gas Emergency Service on 0800 111 999, open windows and avoid switches and flames.
The Gas Safe checks at a glance
Work through these steps in order before you let anyone start on a gas appliance or gas pipework. Each step takes only a few minutes, and together they confirm that the person is registered, that the registration is current and that the job falls within their qualifications.
- Ask the engineer for their Gas Safe ID card and look at the front first.
- Check that the photograph and name match the person standing in front of you.
- Turn the card over and read the list of gas work the engineer is qualified to do.
- Note the registration number and the company name shown on the card.
- Search the Gas Safe Register online using the engineer's name or the company details.
- Compare the register entry with the card, including the company name and the categories of work.
- Confirm that the categories cover the appliance or task you need done.
- Ask for the written record of work, and check that it carries the engineer's registration details.
Why gas work needs a registered engineer
Gas work carries serious risks, including gas leaks, fire and carbon monoxide, which is a gas you cannot see or smell. A badly fitted or poorly serviced appliance can put the people in your home at risk long after the engineer has left. That is why the law requires anyone carrying out gas work to be on the Gas Safe Register, and why the register exists as the place to confirm that an engineer is qualified.
The register is not a formality. A registered engineer has demonstrated the competence needed for the work they say they do, and their registration is tied to specific categories. The register is also how the regulator keeps track of engineers who have stopped being qualified or have been removed. Checking it is the only reliable way to know the position at the time you need it.
Gas safety is also a matter of household safety for the people who live with the appliance, not just the person who owns the property. If you are a landlord, the duties are different and more demanding, and the current requirements are set out on GOV.UK. Check those requirements rather than relying on what someone told you in the past, because rules change.
How to read a Gas Safe ID card, front and back
The card is your first piece of evidence, but it should never be the only one. Look at the front to confirm the identity of the engineer. The photograph should match the person, the name should match the company paperwork, and the card should be in date. If the card looks altered, damaged or reproduced rather than printed, ask for the registration number and check it on the register.
The back of the card is the part most customers ignore, and it is the part that matters most for your job. It lists the types of gas work the engineer is qualified to carry out. An engineer registered for cookers may not be qualified for boiler installation, and one qualified to service gas fires may not be able to work on a gas hob. If the work you need is not listed, ask for an engineer who is qualified for it, even if the one in front of you is pleasant and willing.
A common mistake is to assume that a plumber, heating engineer or handyman is automatically registered. Plenty of skilled people do not do gas work, and plenty of those who do are registered for a narrow set of tasks. A friendly explanation is not a substitute for the card.
Checking the Gas Safe Register and matching the job
Search the register online at the Gas Safe Register's find-an-engineer page. You can usually search by name, company or registration number, and you should compare what the register shows with what the card and the engineer have told you. Confirm the company name, the engineer's name and the work categories. If something does not match, stop until you have an explanation.
| What to check | Where to check it | What it tells you |
|---|---|---|
| Identity | Front of the ID card | Name and photo match the person |
| Work categories | Back of the ID card | Types of gas work they are qualified to do |
| Current registration | Gas Safe Register search | Whether the registration is live today |
| Company match | Register entry and invoice | The firm you are paying is the registered one |
| Job coverage | Register categories against your job | Whether the engineer can legally do the task |
Keep the register entry, or a screenshot of it with the date, in your home file. If the engineer later disputes that they were registered for the work, you will have a record of what you checked and when. Remember that the register shows registration at the time of your search, so check again if the work is scheduled a long time ahead.
If you are unsure which registration covers your property, particularly if you live outside England, Wales and Scotland, ask the Gas Safe Register directly. Do not assume that a registration from one nation automatically answers every question about a property in another.
Certificates and paperwork to ask for after the work
A registered engineer should give you a written record of the work they have carried out, including what was done, any faults found and any safety concerns. The record should carry the engineer's registration details and the company name. Ask for it before the engineer leaves, and do not accept a promise that it will follow later without a date.
For landlords, a gas safety record is a legal requirement for gas appliances in rented accommodation, and the rules about who may carry out the check and how often it must be done are set out on GOV.UK. If you are a tenant, ask your landlord for a copy of the most recent record, and check that the engineer who carried it out was registered for the appliances concerned.
Keep all records together. When you sell or rent a property, buyers and tenants may ask for evidence that gas appliances have been checked and maintained. A tidy file with registration checks, invoices and records makes that conversation far easier.
What to do if the engineer is not registered
If the engineer cannot show a valid card, or the register does not list them for the work you need, stop. Do not let them start, and do not pay for work that has not been done properly. Ask for the engineer's details in writing, including their name and company, so that you can take the matter further if needed.
If an unregistered person has already carried out gas work on an appliance in your home, do not use the appliance until a registered engineer has checked it. Ask a Gas Safe registered engineer to inspect the work, and if you have any concern about a leak or a fault, treat it as an emergency. Open windows, avoid operating switches and flames, leave the property and call the National Gas Emergency Service on 0800 111 999.
You should also tell the Gas Safe Register about the concern so that it can look into the matter. For wider consumer problems, Citizens Advice can explain your options, and our guide on how to spot a rogue trader covers the warning signs that often appear alongside unregistered work.
Red flags that go beyond the ID card
Some warning signs are not about the card at all. They are about the way the engineer and the business behave. Pay attention to these, because a person who avoids basic checks is unlikely to be more open about the work itself.
- Reluctance to show the ID card, or an explanation that the card is "at the office".
- A request to pay cash for gas work, with no invoice or receipt.
- Claims to be "gas trained" or "fully qualified" without a card or register entry to support the claim.
- Work on a boiler, cooker or fire that falls outside the categories listed on the card.
- Pressure to replace an appliance on the spot, with no written explanation of the fault.
- A refusal to put the findings and the recommended work in writing.
When the warning signs appear together, step back and get a second opinion from a different registered firm before you agree to anything. A genuine engineer will not be offended by that request, and most will explain the issue in plain language if you ask.
Questions to ask the engineer before they start
Asking questions before the visit is one of the most useful things you can do. A registered engineer will expect them and will answer in plain language. A reluctant answer tells you something too, so note how the engineer responds as well as what they say.
- Which categories of gas work does your registration cover, and do they include this appliance?
- What exactly will you check, test or replace, and what will you need to isolate first?
- Will you give me a written record of the findings, and will it include any safety concerns?
- If you find a fault I did not expect, what will you do, and how will you explain the cost before proceeding?
- Will the appliance be left safe for use, and what should I do if I notice a problem afterwards?
- Who should I contact if I have a question about the work once you have left?
Pay attention to the answers about faults and extra work in particular. Gas repairs can turn up a second issue once an appliance is opened up, and a good engineer will explain the options, the safety implications and the cost before carrying out additional work. An engineer who starts work on an appliance and then asks for a large sum without explaining the reason has not met that standard.
If the engineer recommends replacing an appliance, ask for the reasons in writing, including the test results or the fault that led to the recommendation. Replacement is sometimes the right answer, but it is also a large purchase. Get a second opinion from a different registered firm if the reasons are unclear, particularly if the appliance is only a few years old or has recently been serviced.
Think about the timing as well. Routine servicing and gas checks can be planned, which gives you time to compare engineers and to check registrations calmly. Emergency visits happen when you have least time to think, so keep a list of registered firms you trust before anything goes wrong. That list is also useful if an engineer you have already used cannot return.
What to do next: finding a registered engineer
Start by listing the gas appliances in your home and any work you expect to need, such as a service, a repair or an installation. That list helps you check whether an engineer's categories match the job, and it helps you ask better questions when you call.
When you look for a plumbing or heating firm, check the Gas Safe credentials before you compare prices. You can browse firms through the plumbing services category or the heating equipment category, which is a useful starting point for boiler and heating work. Use the directory to shortlist firms, then run the register check on each one you are considering. The full list of categories is there if you need a related trade.
If the work also involves electrical wiring near the appliance, check that engineer's electrical registration separately. Our guide on how to choose an electrician explains the schemes and certificates to look for.
Frequently asked questions
Can a gas engineer work on my boiler if they only cover some of the categories?
They can only carry out the work their registration covers. Read the categories on the back of the card and compare them with the job. If the boiler work needs a category the engineer does not hold, they should not carry it out. Ask them to name the category that covers the task, then check the register entry yourself. An engineer who is honest about their limits is far better than one who does work outside their qualifications.
Is every plumber automatically Gas Safe registered?
No. Many plumbers do not carry out gas work, and those who do may be registered only for certain tasks. Plumbing and gas work overlap in places, but registration is specific. Always check the register directly for any gas task, rather than assuming that a plumber's general experience or a business name covers it.
What should I do if I smell gas?
Act immediately. Open windows and doors, avoid operating switches, electrical devices and flames, and leave the property. Call the National Gas Emergency Service on 0800 111 999, which is free and available at all hours. If anyone is in danger, or there is a fire, call 999. Do not return to the property until you have been told it is safe.
Do I need a certificate after a boiler service?
Ask for a written record of the service in every case. It should show what was checked, any faults found, what was done and the engineer's registration details. Landlords have specific legal duties for gas appliances in rented homes, and the requirements are set out on GOV.UK. For your own home, a written record is valuable evidence if a problem appears later.
What if I only have an engineer's name and company name?
Search the Gas Safe Register using the name and company details, and compare the results with the company that has sent you the invoice or quote. If the search does not return a match, ask the engineer for their registration number and check it directly. Do not accept a screenshot or a copy of a card from anyone as the only proof of registration.
Does a Gas Safe card prove the work will be good?
No. The card shows that the engineer was registered when you checked, and that the registration covers the categories listed. It does not guarantee the quality of any particular job. Combine the card check with references, a written quote and a written record of the work to judge the outcome for yourself.
Sources and further reading
- Gas Safe Register – the official register for gas engineers, with guidance for households and landlords.
- Gas Safe Register find an engineer – the search page for checking a registered engineer.
- Health and Safety Executive – the regulator for workplace health and safety, with general gas safety information.
- GOV.UK consumer protection rights – the official summary of your rights when you buy services.
- Citizens Advice consumer service – free help if work has been carried out badly or by an unregistered trader.
This article is general information, not legal, financial or professional advice. Rules and prices change, so check the official sources above before you act.