Gas Safety Certificate — London
Gas Safety Certificate (CP12) in London
Landlord Gas Safety Records from £55, issued same day by Gas Safe registered engineers. Every gas appliance, flue and piece of pipework checked to the Gas Safety (Installation and Use) Regulations 1998. Same-week appointments across all 33 London boroughs.
From £55
Single appliance CP12 in a flat
12 months
Legal inspection interval
28 days
Deadline to give existing tenants a copy
2 years
Minimum time records must be kept
Overview
What a Gas Safety Certificate is, and the legal duty behind it
A Gas Safety Certificate — still widely known by its old form number, CP12, and correctly termed a Landlord Gas Safety Record — is the document a Gas Safe registered engineer issues after inspecting every gas appliance, flue and piece of installation pipework in a property. It confirms each item has been checked and is safe to use, and it records the result against each appliance individually.
The legal basis is the Gas Safety (Installation and Use) Regulations 1998. Under these regulations, any landlord letting a residential property containing a gas appliance, flue or gas pipework must have the installation checked for safety at intervals of not more than 12 months by an engineer registered on the Gas Safe Register. A copy of the record must be given to existing tenants within 28 days of the check, and to new tenants before they move in. Records must be kept for a minimum of 2 years.
This duty applies regardless of who owns the boiler, hob or fire — if a landlord lets a property that contains gas appliances, the annual check is a legal requirement, not a recommendation. Homeowners occupying their own property are not covered by this duty, though the same safety principles make an annual check a sensible precaution for any home with gas appliances.
Scope of inspection
What we check during a Gas Safety inspection
Every gas appliance, flue and length of pipework in the property is inspected and tested. Nothing is assumed safe because it looks fine — each check follows the standard Gas Safe procedure for that appliance type.
Gas boiler and heating appliances
The boiler is inspected for correct operation, safe combustion, adequate ventilation, and correct flue termination. Flame picture, burner pressure and safety devices such as the flame failure device are checked.
Gas hobs and cookers
Each burner is checked for correct ignition, flame picture and stability. The appliance is checked for stability, correct installation, and adequate ventilation in the room where fitted.
Gas fires
Fixed gas fires are checked for safe operation, correct flue or chimney function, and adequate ventilation. Spillage and flue flow tests are carried out where the appliance type requires them.
Flues and chimneys
Every flue serving a gas appliance is checked for a sound structure, correct termination position, and freedom from blockage or damage that could cause dangerous products of combustion to enter the property.
Gas pipework and installation pipework
Visible gas pipework throughout the property, from the meter to each appliance, is inspected for corrosion, damage, and correct jointing. A tightness test confirms there are no leaks in the system.
Meter and emergency controls
The gas meter installation and the emergency control valve are checked for safe, accessible operation, and that a suitable notice on how to act if a tenant smells gas is available where required.
Ventilation and air supply
Airbricks, vents and other permanent ventilation openings serving gas appliances are checked to confirm they are unobstructed and provide the air supply the appliance needs to burn safely.
Carbon monoxide alarms
Where required, we check that a carbon monoxide alarm is fitted in rooms containing a gas appliance and advise on compliant positioning, in line with Smoke and Carbon Monoxide Alarm Regulations.
Legal duty
Who legally needs a Gas Safety Certificate, and when
The duty to obtain an annual Gas Safety Certificate sits with the person letting the property, not the tenant. It applies from the day a property with gas appliances is first let, and every 12 months thereafter for as long as it remains let.
Private landlords
Anyone letting a residential property with a gas supply — a single flat, a whole house, or a portfolio — must arrange an annual Gas Safety Certificate for every property let, with no exceptions for short lets.
Letting agents managing properties
Where a letting agent manages the property on the landlord's behalf, the legal duty still sits with the landlord, but agents typically coordinate the annual check and keep the compliance calendar on the landlord's behalf.
HMO (House in Multiple Occupation) landlords
HMOs require the same annual gas safety check as any other let property, and gas safety compliance is checked as part of HMO licensing inspections by the local council.
Holiday let and Airbnb hosts
Properties let on a short-term or holiday basis with gas appliances fall under the same regulations as standard tenancies and require a current, in-date Gas Safety Certificate.
Housing associations and social landlords
Registered providers of social housing must maintain the same annual gas safety inspection regime across their stock, usually managed through a planned maintenance contract.
Homeowners (recommended, not required)
Owner-occupiers are under no legal duty to obtain a Gas Safety Certificate, but an annual check of the boiler, hob and any gas fire is a sensible precaution against gas leaks and carbon monoxide poisoning.
Non-compliance
What happens without a valid certificate
Letting a property without a current Gas Safety Certificate is a criminal offence. The Health and Safety Executive can prosecute, and penalties include unlimited fines and, in the most serious cases involving injury or death, imprisonment.
A landlord who has not complied with gas safety requirements — including providing tenants with copies on time — cannot validly serve a Section 21 "no fault" eviction notice. This means a lapsed or missing certificate can directly delay or block possession proceedings, regardless of the reason for seeking possession.
Record keeping
Copies to tenants and record retention
A copy of the certificate must reach existing tenants within 28 days of the check. New tenants must receive a copy before moving in, or as soon as reasonably practicable if the check happens mid-tenancy.
Landlords must retain each Gas Safety Certificate for at least 2 years. We recommend keeping a full, unbroken history for as long as the property is let, since mortgage lenders, insurers and letting agents may request evidence of continuous annual compliance beyond the statutory minimum.
How it works
The CP12 process, step by step
From booking to certificate, here is what happens when you book a Gas Safety inspection with us.
01
Book your appointment
Tell us the property type, number of gas appliances and preferred date. We offer same-week appointments across all 33 London boroughs, including early morning and evening slots for tenanted properties.
02
Engineer confirms ID
Every engineer we send carries a Gas Safe ID card. Check it against the Gas Safe Register before work begins — the card shows their licence number, photo and the specific gas work they are qualified to carry out.
03
Full inspection of every appliance
The engineer checks each gas appliance, the flue, pipework, ventilation and emergency controls in turn, following the standard Gas Safe inspection procedure for each appliance type present in the property.
04
Any faults explained clearly
If a fault is found, the engineer explains what it is, whether the appliance can remain in use safely, and what remedial work — if any — is required, with a fixed price quoted before any further work is agreed.
05
Certificate issued same day
On completion, your Gas Safety Certificate is issued the same day, listing every appliance checked, the result, and the engineer's Gas Safe registration number, in PDF format for your records.
06
Copy provided to tenants
We can send the certificate directly to your tenants on your behalf, helping you meet the legal requirement to provide existing tenants with a copy within 28 days of the check.
2025 pricing
Gas Safety Certificate costs in London
Indicative 2025 London prices for a Gas Safety Certificate, inclusive of the engineer\'s visit, inspection of every appliance present, and same-day issue of the certificate. Final price depends on the number and type of appliances and property access. We confirm a fixed price before booking.
| Property / service | Price range (2025) |
|---|---|
| 1-bed flat, single appliance (boiler only) | £55 – £75 |
| 2–3 bed house, boiler + hob | £75 – £95 |
| 3–4 bed house, boiler + hob + gas fire | £95 – £130 |
| HMO (per property, multiple appliances) | £110 – £180 |
| CP12 + annual boiler service combined | £120 – £160 |
These ranges reflect the London market in 2025. Any remedial work identified during the inspection is always quoted separately and agreed before it is carried out — never bundled into the certificate price without your approval.
Choosing an engineer
How to choose a legitimate Gas Safe engineer and avoid scams
Gas safety compliance only protects you and your tenants if the certificate is genuine and the engineer competent. Here is what to check before booking, and the warning signs of a certificate that will not hold up if challenged.
Always check the Gas Safe Register
Every legitimate engineer carries a Gas Safe ID card and appears on the official Gas Safe Register. You can check any engineer's licence number, photo and the categories of gas work they are qualified for at gassaferegister.co.uk before they attend. Never accept a certificate from someone who cannot produce a current card.
Beware of backdated or copy-paste certificates
A genuine Gas Safety Certificate lists the actual appliances present, their individual results, and is dated to the day of inspection. If a certificate looks identical to one from a previous year, lists an appliance that is not actually in the property, or is offered without an engineer visiting, treat it as invalid — it will not protect you legally and puts tenants at real risk.
Watch for unnecessary remedial upsells
A small number of engineers use the CP12 visit to recommend expensive and unnecessary remedial work. Ask for a written explanation of any fault found, referencing the specific regulation or defect, and get a second opinion for any quote over a few hundred pounds before authorising work.
Combine with your annual boiler service
Since an engineer already needs to inspect the boiler as part of the CP12, booking the annual boiler service on the same visit avoids a second call-out charge and keeps your maintenance and compliance records aligned to the same date each year.
Keep a compliance calendar, not just a certificate
The certificate on its own does not prove you served copies to tenants on time. Keep a simple record of the inspection date, the date the copy was given to each tenant, and the renewal due date, so you can demonstrate full compliance if a Section 21 notice is ever challenged.
Red flags to walk away from
A quote significantly below market rate with no appliance-by-appliance detail, an engineer unwilling to show ID, pressure to pay cash with no invoice, or a certificate issued without the engineer actually testing every appliance present, are all signs to find a different engineer.
Get started
Book your Gas Safety Certificate today
Same-week appointments across all 33 London boroughs. Gas Safe registered engineers, fixed price confirmed before booking, and your certificate issued the same day. We can also send a copy directly to your tenants on your behalf.
Common questions
Gas Safety Certificate London: frequently asked
What is a Gas Safety Certificate (CP12)?
A Gas Safety Certificate — often referred to by its old form number, CP12, and formally known as a Landlord Gas Safety Record — is a document issued by a Gas Safe registered engineer confirming that every gas appliance, flue and piece of pipework in a rented property has been inspected and found safe to use. It records the appliance checked, the location, the outcome of the safety checks, and the engineer's Gas Safe registration number. Landlords are legally required to obtain one every 12 months under the Gas Safety (Installation and Use) Regulations 1998.
Is a Gas Safety Certificate a legal requirement?
Yes, for landlords. Under the Gas Safety (Installation and Use) Regulations 1998, any landlord who lets a property with gas appliances, pipework or a flue must have them checked annually by a Gas Safe registered engineer. This applies to houses, flats, HMOs, and holiday lets. Homeowners who live in their own property are not legally required to have an annual gas safety check, though it is strongly recommended for the same reasons the law exists for tenants — carbon monoxide and gas safety.
How much does a Gas Safety Certificate cost in London?
In London in 2025, a Gas Safety Certificate typically costs from £55 for a single appliance in a flat, rising to £75–£110 for a house with a boiler, gas hob and gas fire. Combining a CP12 with an annual boiler service is usually more cost-effective than booking them separately, typically £120–£160 for both. Prices vary based on the number of appliances, property size and access. We provide a fixed price before any engineer attends.
How long does a Gas Safety Certificate last?
A Gas Safety Certificate is valid for 12 months from the date of issue. The check must be repeated every 12 months for as long as the property continues to be let with gas appliances present. Landlords should book the renewal inspection a few weeks before expiry to avoid any gap in compliance, particularly where a mortgage lender or letting agent requires evidence of a current, in-date certificate.
What happens if a landlord does not have a valid Gas Safety Certificate?
Letting a property without a valid, in-date Gas Safety Certificate is a criminal offence under the Gas Safety (Installation and Use) Regulations 1998. The Health and Safety Executive (HSE) can prosecute, with penalties including unlimited fines and, in serious cases, imprisonment. In addition, a landlord who has not complied with gas safety requirements — including serving copies of the record on tenants — cannot validly serve a Section 21 "no fault" eviction notice, which can significantly delay repossession proceedings.
When must a copy of the Gas Safety Certificate be given to tenants?
A copy of the current Gas Safety Certificate must be given to each existing tenant within 28 days of the check being carried out. For new tenants, a copy must be provided before they move in, or as soon as reasonably practicable if the check was carried out during a tenancy. Landlords should keep proof of when and how each record was issued to tenants, as this evidence is required to serve a valid Section 21 notice.
How long do I need to keep old Gas Safety Certificates?
Landlords are legally required to keep copies of Gas Safety Certificates for at least 2 years from the date of issue. In practice, we recommend keeping the full history for as long as you own the rental property, as some mortgage lenders, insurers and letting agents request evidence of continuous, unbroken annual compliance going back further than 2 years.
Do homeowners need a Gas Safety Certificate?
No. The legal duty to obtain an annual Gas Safety Certificate applies to landlords letting a property, not to homeowners occupying their own home. However, we recommend homeowners have their gas appliances checked periodically — particularly older boilers, gas fires and gas cookers — since faulty appliances, flues or pipework present the same carbon monoxide and gas leak risks regardless of tenure. Many homeowners choose to combine this with an annual boiler service.