How to Check if an Engineer Is Gas Safe Registered
Check the Gas Safe Register online or by phone, then read both sides of the ID card.
Search the Gas Safe Register at gassaferegister.co.uk by licence number, business number or postcode, or call 0800 408 5500. Then check the engineer's ID card: the front shows their photo, licence number and expiry date, and the back lists the types of gas work they are qualified to do.
Published 28 September 2026 · Written by the Emergency Plumb engineers
How do you check if an engineer is Gas Safe registered?
Search for the engineer or their business on the Gas Safe Register website, gassaferegister.co.uk, or call the Register on 0800 408 5500. Then ask to see their Gas Safe ID card, and check both sides: the front shows who they are, and the back shows which types of gas work they are qualified to do. It takes two minutes and it is free.
Why does Gas Safe registration matter?
In the UK it is against the law for anyone to do gas work for money unless they are on the Gas Safe Register. That includes fitting, repairing or servicing a boiler, cooker, gas fire or gas pipework. The rule exists because badly done gas work can cause leaks, fires, explosions and carbon monoxide poisoning. Carbon monoxide has no smell or colour, so you cannot tell it is there. Checking an engineer before they start is the simplest way to protect your home.
Checking the Gas Safe Register online or by phone
On the Register's website you can search by the engineer's licence number, by the business registration number, or by business name or postcode. The result should show the business name, whether the registration is current, and the kinds of work its engineers can do. If you would rather speak to someone, the Register's phone line will check for you. Our own business registration number is 932798, so you can check Emergency Plumber London Ltd before we arrive. Our guide on how to choose a plumber covers the other checks worth making.
What to check on the front of the Gas Safe ID card
Every registered engineer carries a Gas Safe ID card, and you are entitled to ask to see it. On the front, check three things. First, the photo: it should be the person standing in front of you. Second, the licence number: this is the engineer's own number, and you can type it into the Register's website. Third, the expiry date: the card must be in date. The card also carries the name of the business the engineer works for. If someone will not show you their card, do not let them work on your gas.
Why the back of the card matters most
The back of the card lists the categories of gas work the engineer is currently qualified to do. Gas Safe registration is not one single qualification. An engineer might be qualified for boilers but not gas fires, or for natural gas but not LPG, which is bottled gas. Some are qualified for homes, and some only for commercial buildings. So check that the job you need is on the list. If you are having a gas hob fitted, the card should show cookers. If it is a boiler, it should show boilers or central heating. An engineer who is registered, but not for the work you need, is not allowed to do that job. The Register's website shows the same categories, so you can check them before the engineer even arrives.
What is a gas safety record (CP12)?
A gas safety record is the document a Gas Safe engineer gives you after checking your gas appliances and pipework. Many people still call it a CP12, after the name of an old form. It lists each appliance checked, where it is, what was tested, including the flue and whether it burns gas safely, and any faults found. It also records the engineer's name, their registration number and the date. A one-appliance gas safety certificate costs £79 with us, and our guide on gas safety certificate cost explains what affects the price.
Gas safety checks for landlords and homeowners
If you let out a home in England, Scotland or Wales, the law requires you to have every gas appliance, fitting and flue you provide checked by a Gas Safe registered engineer every twelve months. You must give a copy of the gas safety record to existing tenants within 28 days of the check, and to new tenants before they move in. You must keep each record for at least two years. The tenant's own appliances are not covered, but the pipework feeding them is. If you are a tenant and have not seen a gas safety record, ask your landlord or letting agent for it. If you own your home, no law says you must have a yearly gas safety check, but it is still a good idea, especially for older boilers, gas fires and cookers, and for any home with young children or older people. A yearly boiler service by a Gas Safe engineer checks that the boiler is burning gas properly and that the flue is taking fumes safely outside. Fit a carbon monoxide alarm in every room with a gas appliance, and test it the way the instructions say. An alarm is cheap, and it is the only way to know carbon monoxide is there.
What to do if something is not right
If the name, number or photo does not match, or the Register does not list the right type of work, do not let the work go ahead. You can report someone doing illegal gas work to the Gas Safe Register. And if you ever smell gas, turn off the supply at the meter if you can, open the windows, leave and call the National Gas Emergency Service on 0800 111 999. For any gas work with us, the price is agreed in writing before we start, and a boiler service is £89.
How to Check if an Engineer Is Gas Safe Registered, your questions
How do I check a Gas Safe number?
What should a Gas Safe ID card show?
Is a CP12 the same as a gas safety certificate?
Do landlords need a gas safety certificate every year?
Is it illegal to use an engineer who is not Gas Safe registered?
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