Buyer guide
Required if…Do I need a gas safety check?
Landlords: yes. Every 12 months by law with a certificate. Businesses: the law says maintain gas appliances safely. An annual service by a Gas Safe engineer is how you prove it. The "commercial gas certificate" is not a statutory document. Who must be Gas Safe registered and what it costs. And what you should not be sold.
Applies to: Great Britain under the Gas Safety (Installation and Use) Regulations 1998. Northern Ireland has its own 2004 Regulations with the same effect.
Looking for the technical detail? Read the version for professionals → GSIUR 1998 and Gas Safe registration categories. BS 6173 and the IGEM/UP standards. Commercial catering ventilation interlocks.
Landlord of a rented home? Annual gas safety check by a Gas Safe engineer and the CP12 to the tenant. That is the law. No discussion.
Business with gas? The law says keep it safe. There is no statutory "commercial gas certificate". Annual servicing by a correctly registered engineer is how you prove the duty is met. For a commercial kitchen it is not optional in any practical sense.
Where are buyers oversold? "Commercial gas certificates" sold as a legal document. Engineers without the right registration category. Service plans on multi year terms for what is one visit a year.
What the law actually requires
Regulation 36 of the Gas Safety (Installation and Use) Regulations 1998 says landlords must have every gas appliance and flue they provide checked every 12 months by a Gas Safe registered engineer. They must keep the record for two years. Existing tenants get a copy within 28 days and new tenants get one before they move in. Since 2018 the check can be done up to two months early without losing the anniversary date.
Regulation 35 says employers and self employed people must keep gas appliances and flues and pipework at their premises in a safe condition. Regulation 3 says any work on gas must be done by a Gas Safe registered business and the engineer must be registered for that category of work. Regulation 4 and the Health and Safety at Work Act put the general duty on anyone in control of premises. "Maintained in a safe condition" is the duty. Annual servicing to the manufacturer's instructions is how it is evidenced.
Where a commercial kitchen has mechanical ventilation, BS 6173 requires the gas supply to be interlocked with the extract so the gas cannot flow if the ventilation fails. Gas Safe engineers treat a missing interlock as "at risk" under the Gas Industry Unsafe Situations Procedure. It is one of the few upgrades on this site that is effectively mandatory.
Commercial insurers require annual servicing by a Gas Safe engineer and will ask for the record. Catering insurers especially. Commercial leases almost always require the tenant to maintain gas installations in the demise and to provide evidence on request.
Northern Ireland: the Gas Safety (Installation and Use) Regulations (Northern Ireland) 2004 impose the same duties.
What this means for your premises
Rented home you let: annual CP12. Non negotiable.
Office or shop with a gas boiler: annual service by a commercially registered engineer. A domestic registered engineer can do it where the boiler is a domestic type unit under 70 kW. Ask which applies. Keep the service report.
Restaurant or café or takeaway or pub: annual service of every appliance by a catering registered engineer. The ventilation interlock in place. Flue and ventilation checked. This is the premises type where things go wrong and where the engineer's registration category matters most.
LPG: its own registration category. Check the engineer holds it.
Your options
Landlords
Book the annual check with any Gas Safe registered engineer. Use the two month early window so the date never slips. Get the CP12 and send it to the tenant. Keep it for two years.
Businesses
One visit a year by a Gas Safe engineer registered for your category of work. Appliances serviced to the manufacturer's instructions. Installation tightness tested. Flues and ventilation checked. A written record issued. Pay per visit or take a one year agreement.
Before you book, check the card. Every Gas Safe engineer carries an ID card listing the categories of work they are registered for. A domestic only engineer cannot legally service your commercial catering equipment. Check the card and check the register online.
Commercial kitchens without an interlock: get it fitted. It is a one off cost and it stops your gas being condemned on the next visit.
What it should cost
Landlord CP12 for a home with a boiler and one or two appliances: £90. Commercial service for a small premises with one or two appliances: £160. Commercial kitchen with several appliances: £400 for the smallest and £560 for 5 to 19 staff. Ventilation interlock supplied and fitted: £650. A boiler service and a landlord check on the same visit is usually cheaper than two visits.
Figures are typical prices taken from published commercial price guides and checked October 2026. Same method on every page. Larger or more complex premises sit above them.
What you shouldn’t be sold
- A "commercial gas safety certificate" as a legal requirement. There is not one. What the law requires is maintenance by a registered engineer and a record of it. The record matters. The word "certificate" does not.
- An engineer without the right category. Domestic registration does not cover commercial or catering work. Ask to see the card.
- A multi year service plan. One visit a year. Nothing about that needs a term.
- Appliance replacement on the strength of "at risk". "At risk" means a defect exists that needs fixing. It is not a condemnation. It often means a part and not a new unit. Get the fault in writing and a second price.
- Boiler cover plans for commercial premises. Priced for domestic peace of mind. Rarely worth it for a business that can call an engineer.
- CO alarms sold as a legal requirement for your shop. They are a legal requirement for landlords of homes. Sensible everywhere and they cost £20.
Check what else your business needs
Gas is one of the specific assessments that hangs off your general risk assessment. Kitchens also need the fire risk assessment to reflect the cooking risk and a wet chemical extinguisher. Run the Compliance Check for the full picture.
Quick answers
- Is an annual gas safety check a legal requirement?
- For landlords of rented homes, yes. Every 12 months by a Gas Safe registered engineer, with a Landlord Gas Safety Record (CP12) given to the tenant. For businesses the law requires gas appliances and flues and pipework to be maintained in a safe condition. It does not set a 12 month interval. Manufacturers and the HSE expect annual servicing and it is the only practical way to prove the duty is met.
- What is a CP12?
- The Landlord Gas Safety Record. It is the form a Gas Safe engineer completes after the annual landlord check. It must be given to existing tenants within 28 days and to new tenants before they move in. It is kept for two years. It is a landlord document. There is no statutory equivalent for commercial premises.
- Do I need a commercial gas safety certificate?
- There is no statutory commercial gas certificate. What you need is evidence that a Gas Safe engineer with the right commercial qualifications has serviced and checked the appliances and installation. Usually annually. Engineers issue a commercial gas safety record or service report for that. Insurers and landlords often ask for it, so keep it.
- Who can work on gas?
- Only a Gas Safe registered engineer, and only one whose registration covers the type of work. Domestic or commercial or catering or LPG. A domestic registered engineer cannot legally work on a commercial kitchen. Check the ID card and the register at gassaferegister.co.uk.
- How much does a gas safety check cost?
- A landlord CP12 for a home with a boiler and one or two appliances is £90. A commercial service on a small premises with one or two appliances is £160. A commercial kitchen with several appliances is £400 for the smallest and £560 for 5 to 19 staff. The interlock and ventilation check for a kitchen is extra if it has not been done.
- Do I need a gas interlock in my commercial kitchen?
- If your kitchen has mechanical extract ventilation, BS 6173 and the Gas Safe technical bulletins require the gas supply to be interlocked with the ventilation so the gas shuts off if the extract fails. An engineer finding no interlock will classify the installation as at risk. It is one of the few mandatory upgrades in small business compliance.
- Do I need a carbon monoxide alarm?
- Landlords in England must fit a CO alarm in any room with a fixed combustion appliance other than a gas cooker. Scotland and Wales have similar rules. For commercial premises it is not a specific legal requirement. It is cheap and expected by insurers and covered by your general risk assessment.
Find and check
Who can I use for this?
We do not recommend suppliers. Here is the official register and what to check before you book.
The register
- Gas Safe Register find an engineer The only legal register. Check the categories on the card.
Check
- Gas Safe registration with the right category. Commercial or catering for a business. Domestic is not enough.
- The ID card in person or the number checked on the register.
- For a kitchen, experience with ventilation interlocks.
Ask
- Which categories are on your card?
- What is the price for the service and the safety check together?
- If something is "at risk", will you give me the fault in writing before you quote?
Insist on
- A written record after every visit.
- For landlords, the CP12 with the two month early window used so the date never slips.
- One visit a year. No multi year plan.
General information about UK compliance, written for the person paying the bill. Not legal advice. If your situation is unusual, get a professional to look at it. See our editorial standards.