If you let a property with gas appliances, the annual gas safety check is one of your most important legal duties. Get it right and it is a simple yearly routine. Miss it and you risk your tenants' safety and enforcement action. This guide explains what the law requires, what the engineer checks, what the record must show and how to stay organised. Our Gas Safe registered engineers carry out landlord checks every week across Surrey, Sussex and Kent.
“The landlords who never have a problem are the ones who diarise the date and book early. Combine the check with a service and you protect your tenants, your boiler and yourself in one visit.”
1. Know what the law requires of you
In Great Britain, landlords' gas duties come from the Gas Safety (Installation and Use) Regulations 1998. They are clear and they are not optional. In broad terms, you must:
- Maintain. Keep the gas appliances, fittings and flues you provide in a safe condition.
- Check. Have every gas appliance and flue checked by a Gas Safe registered engineer every 12 months.
- Record. Keep a record of each check for 2 years.
- Share. Give tenants a copy within 28 days of the check, and new tenants a copy before they move in.
These duties cover most residential lets, including houses, flats, rooms in shared houses and holiday lets. Appliances a tenant owns and brings with them are generally their responsibility, but you may still be responsible for the pipework and flues serving them.
This is a general overview, not legal advice. The official HSE guidance for landlords on gas safety is the best place to check the detail for your situation.
2. Understand what the engineer checks
A gas safety check looks at each appliance and flue you provide. Boilers, gas fires, cookers and hobs are the most common. The engineer works through a set of tests to confirm each one is safe to use at the time of the visit.
- Gas tightness. Testing the installation pipework for leaks.
- Gas rate or burner pressure. Making sure each appliance burns the right amount of gas for its specification.
- Flue and chimney. Confirming combustion products are removed safely and the flue is sound and correctly terminated.
- Ventilation. Checking appliances that need an air supply have enough of it.
- Safety devices. Confirming that flame failure devices and similar protections work.
- Combustion. Usually measured with a flue gas analyser to show the appliance burns cleanly.
Any defects are recorded and classified by how serious they are. If an appliance is dangerous, the engineer will explain the risk and, with your permission, disconnect it or make it safe. They will note exactly what was done on the record.
If you or your tenants smell gas, turn off the supply at the meter if it is safe to do so, open windows, avoid electrical switches and naked flames, leave the property and call the National Gas Emergency number on 0800 111 999. It is free and open 24 hours a day. National Gas lists all gas emergency contact numbers by region.
3. Make sure the record contains everything it should
After the check, the engineer gives you a gas safety record. Most are now digital, which makes them easy to forward to tenants and agents. A complete record will show:
- The date of the check and the property address.
- The name and address of the landlord or managing agent.
- Each appliance and flue checked, its location and the result.
- Any defects found and the action taken.
- The engineer's name, signature and Gas Safe registration number.
Read it properly when it arrives. If anything is marked as a defect or carries advice, act on it promptly and keep evidence of the follow-up work.
Defects are not something to leave until next year. An appliance classed as at risk or immediately dangerous should not be used until it is put right, and our boiler and gas appliance repairs team can usually fix the problem on the same visit or soon after. Once the work is done, keep the paperwork with the record so the story is complete.
Many people still call the gas safety record a “CP12”. That was the name of an old form, and the term stuck. Whatever it is called, what matters is that it records a full check by a Gas Safe registered engineer.
4. Give the record to your tenants on time
Existing tenants must receive a copy within 28 days of the check. New tenants must have a copy before they move in. For some short lets, such as holiday lets, the record can instead be displayed clearly in the property.
Email is fine for most tenancies, provided the tenant has agreed to receive documents that way. Keep proof that you sent it. A valid gas safety record also forms part of the paperwork needed for some tenancy processes in England, so a missing one can cause problems later.
The government's page on landlord safety responsibilities for tenants summarises what renters are entitled to, which is a helpful way to see your duties from the other side.
5. Plan your timing and keep good records
The check must take place every 12 months. To make planning easier, the rules let you book the check up to two months before the deadline and keep the original expiry date, so booking early does not cost you time. Book earlier than that and the 12-month cycle resets from the new date.
You must keep each record for 2 years. Many landlords keep them for longer alongside servicing paperwork, because a complete history makes it easy to show you have met your duties. Digital copies are fine, as long as you can produce them when asked.
- List every gas appliance and flue you provide in each property.
- Put the expiry date of each record in your diary with a reminder two months ahead.
- Book the check and give tenants reasonable notice in line with the tenancy agreement.
- Send the record to tenants within 28 days, and to new tenants before they move in.
- Deal with any defects or advice straight away.
- Store the record securely for at least 2 years.
6. Know the difference between a check and a service
A gas safety check confirms appliances are safe at the time of the visit. A full annual boiler service and maintenance visit goes further, cleaning and adjusting components so the boiler keeps running reliably and efficiently. You can read what that involves in our guide to what happens during a boiler service.
You have a duty to maintain appliances in a safe condition, and manufacturers usually require an annual service to keep the warranty valid. That is why most landlords book both together. It saves a second visit, reduces disruption for tenants and catches wear before it becomes a breakdown.
“Ask for the check and the service on the same visit, and send the tenant a reminder the day before. Most failed appointments we see come down to nobody being home to let us in.”
7. Check your engineer — and handle access problems properly
Only a Gas Safe registered engineer can legally carry out the check, and they must be qualified for the specific appliances involved. Ask to see their Gas Safe ID card, then confirm the 7-digit licence number using the official Gas Safe Register engineer search or by calling 0800 408 5500. The back of the card lists the work they are qualified to do.
Occasionally a tenant will not give access. You must take all reasonable steps to carry out the check, so keep a written record of every attempt, including letters, emails and appointment notices. That paper trail shows you did what you could.
Be patient but persistent. Offer a range of times, explain why the check matters for the tenant's own safety and confirm each appointment in writing. Most access problems are solved by a friendly phone call rather than a formal letter.
Remember that carbon monoxide and smoke alarm duties apply separately and vary across the UK. Our guide to carbon monoxide signs and alarms covers what to look for.
8. Let us take care of it for you
Our Gas Safe registered heating engineers carry out landlord gas safety checks across Surrey, West Sussex, East Sussex and Kent. We can combine them with servicing, explain any issues in plain English and carry out repairs where needed. You receive a digital record ready to forward to tenants and agents.
Whether you own one flat in Crawley or a small portfolio across the region, see the full list of towns and areas we cover and get in touch to book.
Frequently asked questions
Is a CP12 the same as a gas safety record?
Yes, in everyday use. CP12 was the name of an old Gas Safe form, and many landlords and agents still use the term to mean the landlord gas safety record. What matters legally is that every gas appliance and flue you provide has been checked by a Gas Safe registered engineer within the last 12 months.
Do I need a check if the property only has a gas hob?
Yes. If you provide any gas appliance, including a cooker or hob, it must be included in the annual gas safety check, along with the pipework that serves it. Even a property with electric heating needs a check if there is a gas hob, gas fire or any other landlord-supplied gas appliance.
Can my letting agent arrange the gas safety check?
Yes, many agents do, but make it clear in writing who is responsible for booking the check and passing the record to tenants. As the landlord you remain ultimately responsible for making sure it happens on time, so ask the agent for a copy of each record for your own files.
What happens if I miss the gas safety check deadline?
Failing to carry out the annual check is a breach of the Gas Safety (Installation and Use) Regulations 1998 and can lead to enforcement action. More importantly, it leaves your tenants at risk. If you have missed it, book a check with a Gas Safe registered engineer as soon as possible and keep the record safely.
Written by the NW Heating Services team
NW Heating Services installs, services and repairs boilers, heat pumps and underfloor heating for homes and landlords across Surrey, Sussex and Kent, with more than ten years of local experience. Our guides are written from the jobs our engineers carry out every week. More about our team.