What is a gas safety certificate and when do landlords need one?

A gas safety certificate is the everyday name for the Landlord Gas Safety Record, which engineers still call a CP12. It is the written result of the yearly check a landlord must have done on every gas appliance and flue they supply in a rented home. The check is a legal duty under regulation 36 of the Gas Safety (Installation and Use) Regulations 1998, it must be done by a Gas Safe registered engineer, and tenants are entitled to a copy. This guide explains who needs one, how often, what it covers, what it costs and what happens if you do not have one.

What is a gas safety certificate?

Strictly, there is no certificate. The law asks for a record of a gas safety check, and the engineer fills in a standard form with the results. The form was numbered CP12 by CORGI, the body that registered gas engineers before the Gas Safe Register took over in 2009, and the name stuck. Landlord Gas Safety Record, gas safety certificate and CP12 all mean the same document.

The HSE says the record must show:

• a description and the location of each appliance and flue checked;
• the name, registration number and signature of the engineer who did the check;
• the date of the check and the address of the property;
• the name and address of the landlord, or the agent where one is used;
• any defect found and what was done about it;
• confirmation that the checks the regulations require were carried out.

Source: HSE, gas safety check records.

The engineer gives the record a safety outcome for each appliance. A pass means it is safe to use. A fault is classed as Immediately Dangerous, At Risk or Not to Current Standards, and the section below on what happens when something fails explains each one.

Do landlords legally need a gas safety certificate?

Yes, in England, Scotland and Wales. Regulation 36 of the Gas Safety (Installation and Use) Regulations 1998 puts three duties on anyone who lets residential premises with gas:

1. Maintain the gas pipework, appliances and flues you supply in a safe condition.
2. Have a safety check done on each appliance and flue every 12 months by a Gas Safe registered engineer.
3. Keep a record of each check and give a copy to your tenants.

The duty applies to private landlords, housing associations and councils, to houses in multiple occupation, to holiday lets and to rooms let in a shared house. Using a letting agent does not move the duty: the agent can arrange the check, but the landlord is the one prosecuted if it is missed. Northern Ireland has its own regulations with the same effect.

Scotland and Wales add their own layer. In Scotland the yearly check and the record are part of the Repairing Standard, enforced through the First-tier Tribunal. In Wales, since 1 December 2022 a home where the gas duty has been breached can be treated as unfit for human habitation under the Renting Homes (Wales) Act 2016, which can mean no rent is due while it stays that way.

Owner occupiers do not need one. If you live in your own home there is no certificate to hold. You are strongly advised to have the boiler serviced once a year, and our guide to what a boiler service costs covers that.

How often does a gas safety check need doing?

Every 12 months. Until 2018 that caused a problem: book the engineer early and the next deadline moved earlier too, so landlords lost a few weeks every year or left it to the last day. The Gas Safety (Installation and Use) (Amendment) Regulations 2018 added regulation 36A, which works like an MOT. A check done 10 to 12 months after the last one counts as if it were done on the anniversary, so the deadline stays put.

Two conditions come with the window. You must be able to show the previous two checks were done within the required timescales, and HSE guidance says you then keep the records until two further checks have been done, rather than the usual two years.

A new gas appliance fitted by the landlord needs its first check within 12 months of installation. If a property has no gas supply at all, none of this applies, but write that down, because a tenant, a council or a buyer will ask.

What does a landlord gas safety check cover?

The engineer checks every gas appliance and flue that the landlord supplies, and inspects the pipework. For each appliance that normally means:

• the appliance is correctly set and burning safely, usually confirmed with a flue gas analyser;
• the operating pressure or heat input is right for the appliance;
• the flue is complete, clear and carrying the products of combustion out of the building;
• there is enough ventilation for the appliance to burn safely;
• the safety devices, such as the flame failure cut off, work;
• the appliance is stable, secure and fit to use.

The whole gas installation is also given a tightness test at the meter to check for leaks, and the visible pipework is inspected. Appliances the tenant owns are not the landlord's to check, but any flue or pipework they connect to is, so those still appear on the record.

A typical check takes 30 minutes to an hour for a home with one boiler, longer for a property with a boiler, hob and gas fire. The engineer should be able to tell you which appliances are included in the price before they come.

How much does a gas safety certificate cost?

There is no independent survey of landlord gas safety check prices the way there is for a boiler service, so treat every figure, including ours, as a guide. In 2026, price guides published by letting compliance firms put the cost at:

Source: 2026 price guides such as Logbook; London and the South East sit 15 to 30 percent above these ranges. For comparison, a June 2025 Which? survey put the average one-off boiler service at around £79.

What moves the price is the number of appliances, the region, whether the engineer has to travel to a property outside their normal patch, and whether you ask for the check alone or bundle it. Most landlords get the best value by booking the yearly boiler service and the safety check on one visit, since the engineer is already standing in front of the boiler. If you let several properties, ask for a per property price for doing them in one day.

In the West Midlands you can see gas engineers in Birmingham, Wolverhampton, Coventry, Walsall and Dudley, with their Google rating where they have one, before you ask for a price.

What must you give the tenant and when?

• Existing tenants: a copy of the record within 28 days of the check.
• New tenants: a copy before they move in.
• Short lets of under 28 days: a copy can be displayed in the property instead.
• Your own copy: keep it for at least two years, or until two further checks have been done if you use the 10 to 12 month window.

An electronic copy is fine as long as the tenant can get it, it can be printed, it cannot be altered, and it identifies the engineer by a signature, scanned signature, registration number or name. Email it and keep the sent message as your proof.

Until 1 May 2026 this paperwork had a second use in England: a landlord who had not given the tenant the gas safety record could not serve a valid section 21 notice. Section 21 was abolished on that date by the Renters' Rights Act 2025, so that particular trap has gone. The gas duty itself has not changed at all, and a missing record will still count against a landlord in a possession claim, a council inspection or an HSE investigation.

What happens if an appliance fails the check?

Engineers classify unsafe situations under an industry procedure, and the code they write on your record tells you how urgent the problem is.

An ID or AR result does not mean you have broken the law. Failing to act on it does. Regulation 36 requires the landlord to take remedial action, so arrange the repair, have it done by a Gas Safe registered engineer, and keep the invoice with the record. The tenant must not use the appliance in the meantime, and if the boiler is the only heating or hot water you should provide temporary heaters or a repair within days, not weeks.

What are the penalties for not having a gas safety certificate?

Missing the check is a criminal offence, not a civil matter. The HSE enforces the regulations under the Health and Safety at Work etc. Act 1974 and prosecutes landlords who let without a check, who ignore an unsafe result, or who use an unregistered engineer. The courts can impose an unlimited fine and, in the most serious cases, a prison sentence, and sentences in recent cases have included suspended prison terms alongside fines and costs. Councils can also act through housing law, and in Wales the home can be treated as unfit, which can suspend the rent.

The reason the law is strict is that the risk is invisible. HSE figures show around seven people a year die in Great Britain from carbon monoxide poisoning caused by gas appliances and flues that were badly installed, badly maintained or poorly ventilated, and many more are made ill. The early symptoms, headaches, tiredness, nausea and dizziness, are easy to mistake for a virus.

Source: HSE, carbon monoxide awareness.

Is a gas safety check the same as a boiler service?

No, and the HSE says you should not assume one includes the other. A gas safety check tests that each appliance, flue and the pipework are safe and produces the legal record. A boiler service strips, cleans and adjusts the boiler so it runs efficiently, and most manufacturer warranties require one a year. A landlord needs the check by law and should have the service for the boiler's sake. Most engineers will do both on one visit, which is cheaper than two call outs, so ask for the combined price when you book. Our guide to boiler service costs explains what a proper service includes.

Do landlords also need carbon monoxide alarms?

Yes, and the rules sit beside the gas check rather than inside it.

• England: the Smoke and Carbon Monoxide Alarm (England) Regulations 2015, amended from 1 October 2022, require a carbon monoxide alarm in every room used as living accommodation that has a fixed combustion appliance, excluding gas cookers. A faulty alarm must be repaired or replaced once the tenant reports it. Councils can fine up to £5,000 for failing to comply with a remedial notice.
• Scotland: the Tolerable Standard requires a carbon monoxide detector in every room with a fixed combustion appliance, again excluding appliances used only for cooking.
• Wales: the fitness for human habitation regulations require a carbon monoxide alarm in any room with a gas, oil or solid fuel burning appliance, plus mains powered, interlinked smoke alarms on every storey.

Buy alarms that meet BS EN 50291, fit them at head height a metre or two from the appliance, and note the test on your inspection record. Landlords also need the fixed electrics inspected at least every five years: see what an EICR is and how often you need one.

How to arrange a landlord gas safety check

1. Find the date of the last check and book within the two months before the anniversary, so the deadline stays where it is.
2. Book a Gas Safe registered engineer. Search the Gas Safe Register or call it on 0800 408 5500. Ask for a fixed price that names every appliance and flue, and whether the service can be done on the same visit.
3. Give the tenant written notice of the date and time, with at least 24 hours notice. Offer alternatives if they cannot be in.
4. Check the ID card on the day. The back lists the categories of work the engineer is qualified for. Boilers, cookers and fires are separate categories.
5. Read the record before you file it. Every appliance and flue listed, the engineer's name and registration number, and a note against any defect.
6. Give the tenant a copy within 28 days and keep yours for two years. Put the next deadline in your diary now.

If the tenant refuses access, do not force entry. Write explaining the check is a legal duty for their safety, offer two or three dates, keep every letter and message, and record the engineer's wasted visit. The HSE expects a landlord to show they took all reasonable steps, and that paper trail is what proves it.

Find a Gas Safe engineer near you

You can post your gas safety check job free and a local Gas Safe registered engineer comes back to you with a price and a time. Say how many appliances the property has and whether you want the boiler serviced on the same visit, so the price you get back is a real one. You pay the engineer directly, and nothing is taken online.

Or browse local businesses first: gas engineers in Solihull, Birmingham, heating engineers in Wolverhampton or Coventry. If the job is a leak or a radiator rather than gas, see what a plumber charges per hour. For more guides on repairs and costs, see all our home advice.