What is a CP12 gas safety certificate?

A CP12 in plain English

A CP12 is the Landlord Gas Safety Record: the document a Gas Safe registered engineer issues after checking the gas appliances and flues you provide in a rented property. You must have that check done at least every 12 months, give your tenant a copy within 28 days, and keep the record.

"CP12" is the everyday name for it. The duty sits in regulation 36 of the Gas Safety (Installation and Use) Regulations 1998, which requires each appliance and flue to be "checked for safety within 12 months of being installed and at intervals of not more than 12 months since it was last checked". Only a Gas Safe registered engineer can do that check and sign the record.

It is not a boiler service. The CP12 is a legal safety check on the gas you provide; a service is preventative maintenance and is not required by law. Many engineers do both on one visit, but only one of the two satisfies the 1998 Regulations.

The CP12 rules, in one list

What the Regulations and HSE actually require of you:

• Every gas appliance and flue you provide is checked at least every 12 months, and within 12 months of installation.
• The check is carried out by a Gas Safe registered engineer.
• Existing tenants get a copy within 28 days; a new tenant gets one before they move in.
• Keep each record until two further checks have been done, and for two years from the last check where an appliance or flue has been removed.
• Take prompt action to correct any defect the record shows.
• Keep any relevant gas fitting you provide, and any flue serving it, maintained in a safe condition. Regulation 36(2) makes that a separate, continuing duty that the annual check alone does not discharge.
• You can check in the two months before your deadline and keep your original renewal date.
• Appliances your tenant owns sit outside the duty; the ones you provide do not.

How much does a CP12 cost?

There is no set price. The 1998 Regulations create the duty but say nothing about a fee, and neither HSE nor gov.uk quotes a figure, so every Gas Safe registered engineer sets their own price. The table below lists what moves a quote up or down.

Ask for a written quote first: how many appliances are covered, whether a boiler service is bundled in, and whether a return visit costs extra. Get two or three local quotes, and check the engineer's Gas Safe ID card before they start, including the appliance types they are registered for.

What changes the price of a CP12

One thing worth saying plainly: a gas safety check is booked and priced separately from any cover plan, and nothing above is a price we set or charge. Where a plan includes an annual service, our cover plan terms define the record we can provide on completion, a Gas Safety Record, and the landlord version of it, an LGSR. Ask us what applies to your property.

What has to be on the record

HSE sets out what the record must contain: a description and the location of each appliance or flue checked, the name, registration number and signature of the engineer, the date of the check, the address of the property, the name and address of the landlord or their agent, and "any safety-related defect identified and any remedial action taken".

Read it when it arrives. If an appliance you provide is missing, or the registration number is not on it, you do not yet have a complete record.

The two-month rule: book early without losing your date

The Gas Safety (Installation and Use) (Amendment) Regulations 2018 added regulation 36A: "Where a safety check of an appliance or a flue made in accordance with regulation 36(3)(a) or (b) is or was completed within the period of 2 months ending with the deadline date, that check is to be treated for the purposes of regulation 36(3)(a) and (b) as having been made on the deadline date."

So if your record is dated 15 March 2026, your deadline is 15 March 2027, and you can book from 15 January 2027 while keeping 15 March as your anniversary. Booking early leaves room to rebook if the tenant is away. HSE notes the old record must be kept until two further checks have been done.

Who needs a CP12, and who does not

HSE defines a landlord here as "anyone who rents out a property they own under a lease or a licence that is shorter than seven years". That takes in housing associations, local authorities, hotels and B&Bs, colleges and hostels, and it reaches holiday lets.

The duty covers "any gas appliances (permanent or portable), and gas flues that you own and provide for use by your tenants". Appliances your tenant owns sit outside it. If your tenant sublets, the duty stays with you: HSE says "you cannot transfer this responsibility to your tenant who is subletting". A lease of seven years or more falls outside the definition of a lease in regulation 36(1), so the duty does not attach, but HSE adds a caveat: "if there remains an implied tenancy arrangement, such as accommodation is provided as part of a job (eg vicar, publican), then we recommend that you carry out the landlord's duties for the property".

If a letting agent manages the property, the duty can sit with them where the management contract says so. Read your agreement: assuming is not a defence.

What if your tenant will not let the engineer in?

You still hold the duty, and you still cannot force entry. HSE is blunt: "You must not use force to enter the property." What protects you is evidence that you took every reasonable step.

Your tenancy agreement "should allow you access for any maintenance or safety check work that needs to be done". When a visit fails, leave a notice saying an attempt was made, with your contact details, then write explaining that the check is a legal requirement and is for the tenant's own safety, and offer them the chance to book their own appointment.

Keep every letter, email and message. HSE inspectors "will look for repeated attempts to complete the gas safety check", and a court decides whether your action was reasonable.

What happens if the check finds something unsafe

The record must show "any safety-related defect identified and any remedial action taken", and HSE says landlords "must take prompt action to correct any defect shown on the safety check record". A failed check does not pause your duty; it starts a clock.

Under the gas industry's Unsafe Situations Procedure, an engineer classifies a dangerous situation as either Immediately Dangerous or At Risk. HSE notes that both carry the same warning label message: "Danger Do Not Use". Either way the appliance stays off until a Gas Safe registered engineer has repaired and re-checked it. Never use, move or tamper with an appliance carrying that label, and never attempt a gas repair yourself.

If anyone smells gas

HSE's advice, if you suspect a gas leak, is to call the National Gas Emergency Service freephone number 0800 111 999 immediately, open all the doors and windows, and shut off the gas supply at the meter control valve if you know where it is. Do not smoke, do not use a naked flame, and do not turn any electrical switch on or off. Get everyone out of the property and make the call from outside. Make sure your tenants have that number, because they are the ones who will be there when it matters.

What is the penalty for not having a CP12?

Failing to meet the 1998 Regulations is a criminal offence, prosecuted under section 33 of the Health and Safety at Work etc. Act 1974 and enforced by HSE. There is no fixed-penalty ticket for it.

Schedule 3A of the 1974 Act sets the maximum on conviction on indictment at "imprisonment for a term not exceeding two years, or a fine, or both", and a magistrates' court can also impose imprisonment, a fine, or both. Those are ceilings rather than typical outcomes. The practical consequences arrive sooner: a missing record causes trouble with letting agents and weakens your position in any dispute with a tenant.

Does the Renters' Rights Act change any of this?

No. The Renters' Rights Act received Royal Assent on 27 October 2025 and reshapes tenancies in England, ending Section 21 "no fault" evictions. The government's own summary of the Act's measures says nothing about gas safety.

Your CP12 duty stands exactly as before: at least every 12 months, by a Gas Safe registered engineer, copy to the tenant within 28 days, record kept. This is a plain-English summary rather than legal advice, so check the gov.uk guidance for your properties.

CP12, boiler service and cover plan: three different things

Where a cover plan fits in

A cover plan is not a CP12 and never replaces it. What it does is spread the cost of a repair when something fails between checks, which is the bill a landlord cannot plan for.

Smart Plan is a modular service plan from UK Boiler Company Ltd, not insurance: you build your own cover and pay only for the modules you pick. Repairs go through a national network of thousands of Gas Safe registered engineers. Read the conditions below first, because on an older rental boiler the £200 cover limit is the number that matters.

What to know before you sign up

The conditions that shape what a Smart Plan cover plan is worth to a landlord:

• Cover limit for boiler and central heating: up to £500 a year if the boiler is under seven years old, and up to £200 a year if it is over seven years old. Parts and labour are included up to that limit.
• A £95 call-out fee applies in defined cases, paid in advance of us attending.
• In the first 30 days of a new agreement, any call-out you request costs that £95 fee in advance plus payment for any additional works in advance of the works being completed.
• Call-outs run Monday to Friday, 08:00 to 18:00, unless it is a genuine emergency breakdown.
• We aim to get an engineer out to you within two working days, inside those call-out hours.
• The plan is monthly rolling, but once you request a service a 12-month agreement period begins.
• Leaving during that agreement period costs the remaining months, or 75% of the outstanding balance.
• There is a 14-day cooling-off period, and it ends the moment a service is carried out.

CP12 gas safety certificate FAQs

Letting a property with a boiler?

Your CP12 is the legal check. Doing it, giving your tenant a copy and keeping the record is what keeps you compliant. A Smart Plan boiler module spreads the cost of covered repairs between checks, up to your cover limit. A £95 call-out fee applies in defined cases, and a 12-month agreement period begins once you use a service.

Related links

• Landlord boiler cover
• Gas safety: a landlord's responsibilities
• Boiler service cost: what you should pay
• Boiler cover for older boilers
• Ask us about cover for a rental property
• HSE: gas safety for landlords and tenants
• Regulation 36, Gas Safety (Installation and Use) Regulations 1998
• gov.uk: guide to the Renters' Rights Bill