How to Get a Gas Safety Certificate (CP12)
Last updated:
Find a Gas Safe registered engineer via the Gas Safe Register website, book an annual safety check, ensure access to all gas appliances, receive your CP12 certificate, and give a copy to tenants within 28 days (or before move-in for new tenants). The check typically costs £60-£120 and takes 30-60 minutes.
Gas safety is non-negotiable for UK landlords. Every rental property with gas appliances needs a valid Gas Safety Record (commonly called a CP12 certificate) renewed every 12 months. Without one, you face fines up to £6,000, a criminal record, and invalid insurance. This guide covers everything: how to get your certificate, what it costs, how to check or replace one, and what happens if you fall behind.
For more on how often certificates need renewing, see our gas safety certificate frequency guide. For a complete overview of all landlord certificates, read the landlord certificates guide.
Step-by-step: getting your gas safety certificate
Step 1: Find a Gas Safe registered engineer
Only Gas Safe registered engineers can legally work on gas appliances and issue certificates. Use the official Gas Safe Register (gassaferegister.co.uk) to find engineers in your area, or call 0800 408 5500.
You can also search for local Gas Safe engineers through:
- The Gas Safe Register website - the official search tool
- Recommendations from other landlords
- Your letting agent (many have preferred engineers)
- Local trade directories - but always verify Gas Safe registration
Step 2: Verify their registration on Gas Safe Register
Before booking, check the engineer's registration online. Enter their Gas Safe ID number on the register website. Verify they are qualified for the type of appliances you have (some engineers specialise in certain appliance types).
When they arrive, ask to see their Gas Safe ID card. It should show their photo, registration number, expiry date, and the categories of work they are qualified to do. Every Gas Safe card has a unique QR code you can scan to verify it.
Step 3: Book the annual safety check
Schedule the check before your current certificate expires. Many landlords book 10-11 months after the previous check to ensure continuous coverage. Give the engineer details of what appliances are present so they can allocate the right amount of time.
If you book the check in the final month before expiry, the new certificate will still be dated from the actual inspection date. This means booking late can reduce your coverage window. Booking early avoids this problem.
Step 4: Ensure access to all gas appliances
The engineer needs to reach every gas appliance: boiler, hob, oven, fire, water heater. If the property is tenanted, give the tenant advance notice in writing. The engineer must check all appliances to issue a valid certificate.
If a tenant refuses access, document your attempts. Send at least two written requests giving reasonable notice. In extreme cases, you may need to apply to court for access, but a clear paper trail protects you.
Step 5: Engineer conducts safety checks
The engineer will check:
- Gas appliances are safe to use and operating correctly
- Flues and ventilation are working properly and not blocked
- Pipework is sound with no leaks
- Emergency controls are accessible and functional
- Gas pressure and flow rates are within safe limits
This typically takes 30-60 minutes depending on the number of appliances. A property with a single boiler may take around 30 minutes, while a property with a boiler, hob, oven, and gas fire could take up to an hour.
Step 6: Receive your CP12 certificate
If everything passes, the engineer issues a Gas Safety Record (commonly called CP12). This shows which appliances were checked, their condition, and any actions required. Keep this certificate - you will need it for insurance claims, tenant disputes, and compliance checks.
If appliances fail, the engineer may disconnect them for safety. You will need repairs by a qualified engineer before they can be used again. See what to do if your certificate fails below.
Step 7: Check the certificate for issues flagged
Read the certificate carefully. Issues may be marked as:
- Immediately Dangerous (ID): Appliance has been disconnected. Unsafe to use under any circumstances.
- At Risk (AR): Not immediately dangerous but could become so. Needs attention soon.
- Not to Current Standard (NCS): Does not meet current regulations but is not immediately unsafe. Should be addressed at next service.
Step 8: Give a copy to tenants
You must give a copy of the certificate to existing tenants within 28 days of the check. For new tenants, provide it before they move in. Keep proof that you provided it - email is ideal as it creates an automatic record with a timestamp.
Step 9: Keep records for at least 2 years
Retain copies of gas safety certificates for at least 2 years. If there is ever a dispute, prosecution, or insurance claim, you need to prove you were compliant. Digital storage is perfectly acceptable and makes retrieval faster.
LandlordOS stores certificates digitally and uses AI to extract key dates automatically, so you never miss a renewal. See our compliance checklist for all the certificates you need to track.
Managing this yourself?
LandlordOS helps UK landlords stay compliant and organised:
- Automatic compliance reminders for Gas Safety, EICR, EPC
- Document storage with AI-powered certificate reading
- Tenancy tracking and rent management
How much does a gas safety certificate cost?
Gas safety certificate costs vary by the number of appliances and your location. Here are typical prices across the UK in 2026:
| Scenario | Typical cost |
|---|---|
| Single appliance (boiler only) | £60 - £80 |
| Two appliances (boiler + hob) | £70 - £90 |
| Three or more appliances (boiler + hob + fire) | £80 - £120 |
| London / South East premium | £80 - £150 |
| Multi-property discount (per property) | £50 - £70 |
Some engineers offer combined gas safety check and boiler service packages. This can save money compared to booking separately, and helps keep your boiler in good condition. Expect to pay £100-£160 for a combined check and service.
For a detailed breakdown, see our full gas safety certificate cost guide.
How to check a gas safety certificate online
You can verify gas safety information online through the Gas Safe Register. There are several checks you can run:
Check an engineer's registration
Visit the Gas Safe Register website and enter the engineer's licence number. This tells you whether they are currently registered, what types of gas work they are qualified to do, and when their registration expires. Always verify before letting anyone work on gas appliances.
Check a gas safety record
Gas Safe engineers are required to notify Gas Safe Register of all safety checks they carry out. If you need to verify that an inspection took place, contact Gas Safe Register on 0800 408 5500 with the property address and approximate date of the check.
Report concerns
If you suspect someone is working on gas illegally (without Gas Safe registration), report it to Gas Safe Register. Illegal gas work is extremely dangerous and can result in carbon monoxide poisoning, fires, or explosions.
You can also use the LandlordOS compliance checker to verify whether your property meets all current requirements, including gas safety.
Getting a replacement or duplicate gas safety certificate
Lost your gas safety certificate? There are several ways to get a replacement copy:
Option 1: Contact the original engineer
The easiest route is to contact the Gas Safe registered engineer who carried out the inspection. They are required to keep records and should be able to issue a duplicate. There may be a small administration fee (typically £10-£20).
Option 2: Contact Gas Safe Register
If you cannot trace the original engineer (perhaps they have retired or their business has closed), contact Gas Safe Register directly on 0800 408 5500. They hold records of all registered inspections and may be able to provide confirmation that the check was carried out.
Option 3: Book a new inspection
If the records cannot be traced, the safest option is to book a fresh gas safety check. This gives you a new, current certificate and confirms all appliances are safe. Given the relatively low cost (£60-£120), this is often the most practical solution.
To avoid this problem in future, store certificates digitally. LandlordOS lets you upload and store all compliance documents, with AI automatically extracting expiry dates and setting renewal reminders.
What to do if your gas safety certificate fails
If one or more appliances fail the gas safety check, do not panic. Here is what to do:
- Do not use the failed appliance. If it has been classified as Immediately Dangerous (ID), the engineer will have already disconnected it. Do not attempt to reconnect it yourself.
- Get a repair quote. Ask the engineer for details of what needs fixing. Get a quote for the repairs, or ask them to carry out the work if they are qualified for that type of repair.
- Arrange repairs promptly. For ID or AR faults, act within days, not weeks. Your tenant's safety is at risk, and delays could lead to prosecution.
- Book a re-inspection. After repairs, the engineer needs to re-inspect the appliance and confirm it is now safe. Only then will you receive a pass on your Gas Safety Record.
- Inform your tenant. Keep them updated on the timeline for repairs. If heating or cooking is affected, consider whether temporary arrangements are needed.
- Document everything. Keep records of the failure, repair quotes, completed work, and re-inspection. This protects you if questions arise later.
If the cost of repair is high (particularly for old boilers), it may be more cost-effective to replace the appliance entirely. A new A-rated boiler also improves your property's energy efficiency.
Penalties for not having a gas safety certificate
Operating a rental property without a valid gas safety certificate is a criminal offence under the Gas Safety (Installation and Use) Regulations 1998. The consequences are severe:
- Unlimited fine - typically up to £6,000 per offence, but can be higher for repeat offenders
- Criminal record - a conviction that stays on your record
- Prison sentence - up to 6 months for serious breaches
- Invalid insurance - your landlord insurance policy is likely voided without a valid gas safety certificate, leaving you personally liable for any claims
- Cannot serve Section 21 - without a valid gas safety certificate, any Section 21 notice is automatically invalid. This applies until the Renters' Rights Act fully abolishes Section 21 in 2026
- Manslaughter charges - if a tenant is killed by a faulty gas appliance and you did not have a valid certificate, you could face manslaughter charges
- Local authority enforcement - councils can issue improvement notices and prohibition orders on your property
The Health and Safety Executive (HSE) and local authority environmental health teams enforce these regulations. Enforcement has increased in recent years, with landlords prosecuted for both missing and expired certificates.
Use the compliance checker to see whether your property meets all current requirements, or read the full compliance checklist.
Gas boiler registration
When a new gas boiler is installed, the Gas Safe registered installer must register the installation. This involves notifying building control and recording the installation on the Gas Safe Register. Registration confirms the boiler was installed safely by a qualified engineer.
You can check whether your boiler installation is registered on the Gas Safe Register website. Enter the property postcode and the approximate date of installation. If the installation is not registered, contact the installer and ask them to complete the notification. An unregistered installation could cause problems when selling the property or making insurance claims.
Boiler registration is separate from the annual gas safety check. Even with a registered boiler, you still need a valid gas safety certificate renewed every 12 months. For more detail on renewal timing, see our gas safety certificate frequency guide.
LandlordOS tip
Use the same engineer annually if possible. They will know the property, which speeds up checks and helps spot changes over time. Build a relationship with a reliable Gas Safe professional. If you manage multiple properties, ask about portfolio discounts - many engineers offer reduced rates for landlords who book several checks at once.
Frequently asked questions
How do I get a gas safety certificate?
Find a Gas Safe registered engineer via gassaferegister.co.uk, book an annual safety check, ensure the engineer can access all gas appliances, and receive your CP12 Gas Safety Record. You must give a copy to tenants within 28 days and keep records for at least 2 years. The check typically costs £60-£120 and takes 30-60 minutes.
How much does a gas safety certificate cost?
A gas safety certificate typically costs £60-£80 for a single appliance (such as one boiler). For properties with multiple gas appliances (boiler, hob, fire), expect to pay £80-£120. Prices vary by region, with London and the South East at the higher end. Some engineers offer discounts for multiple properties. See our detailed cost guide for more.
Can I get a copy of my gas safety certificate?
Yes. Contact the Gas Safe registered engineer who carried out the original inspection for a duplicate copy. If you cannot trace the original engineer, contact Gas Safe Register on 0800 408 5500. They hold records of all inspections and should be able to help you obtain a replacement.
How do I check a gas safety certificate online?
Visit the Gas Safe Register website at gassaferegister.co.uk and use their online tools. You can verify an engineer's registration by entering their Gas Safe ID number, and check whether an inspection has been recorded for a property. You can also call Gas Safe Register on 0800 408 5500 for verification.
What is a CP12 certificate?
CP12 is the commonly used name for a Landlord Gas Safety Record. It is the certificate issued by a Gas Safe registered engineer after completing an annual gas safety check on a rental property. The official name is Gas Safety Record, but most landlords and engineers still refer to it as a CP12. It records all gas appliances checked, their condition, and any defects found.
How often do I need a gas safety certificate?
Every 12 months. Under the Gas Safety (Installation and Use) Regulations 1998, landlords must have all gas appliances, flues, and pipework checked annually. The certificate expires exactly 12 months from the date of the previous check. Read our full guide on gas safety certificate frequency for tips on timing your renewal.
What happens if I don't have a gas safety certificate?
It is a criminal offence. Penalties include an unlimited fine (typically up to £6,000 per offence), a criminal record, up to 6 months in prison, invalidation of your landlord insurance, inability to serve valid Section 21 notices, and potential manslaughter charges if a tenant is harmed by a faulty gas appliance.
Can I get a replacement gas safety certificate?
Yes. Contact the original Gas Safe registered engineer who performed the inspection and request a duplicate. If you cannot trace them, contact Gas Safe Register directly on 0800 408 5500 as they hold records of all inspections. There may be a small fee (£10-£20) for issuing a duplicate. If records cannot be traced, book a fresh inspection.
Do I need a gas safety certificate for an electric-only property?
No. Gas safety certificates are only required for properties with gas appliances or a gas supply. If your rental property is entirely electric (no gas meter, no gas boiler, no gas hob, no gas fire), you do not need one. You will still need an EICR and an EPC. If you are unsure whether your property has gas, check for a gas meter.
How long does a gas safety check take?
A gas safety check typically takes 30-60 minutes. A single-boiler property may take around 30 minutes. Properties with multiple gas appliances (boiler, hob, oven, gas fire) will take closer to 45-60 minutes. The engineer needs to inspect each appliance, check flues and ventilation, and test pipework.
What is gas boiler registration?
Gas boiler registration means recording your boiler installation with Gas Safe Register. When a new boiler is installed, the Gas Safe registered installer must notify building control and register the installation. This confirms the installation was carried out safely by a qualified engineer. You can check your boiler's registration status on the Gas Safe Register website.