Guide: Gas
Landlord gas safety certificate (CP12): the rules and renewal
Every UK private rental with a gas appliance, pipework or flue must be inspected once every 12 months by a Gas Safe registered engineer under the Gas Safety (Installation and Use) Regulations 1998. The output is the CP12, the Landlord Gas Safety Record. Without one in date you cannot legally let or re-let the property.
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Get matchedWhat the engineer must inspect
- Every flue.
- Every gas appliance owned by the landlord, such as the boiler, hob, oven, fire and water heater.
- The gas pipework, including concealed runs the engineer can reasonably access.
- The ventilation arrangements for each appliance.
- The combustion performance, via flue gas analysis, on every appliance.
The 28-day renewal window
The 1998 regulations allow renewal up to 28 days before the current certificate expires without losing the original anniversary date. Renew earlier than that and the new 12-month clock starts from the inspection date, shortening the cycle. Most landlords aim for the final two weeks before expiry.
Tenant access and the documented attempt
If a tenant refuses access, the landlord is not automatically off the hook. The HSE expects evidence of reasonable attempts (letters or emails, not just verbal). Keep dated copies. The CP12 cannot be issued without an inspection, but documented attempts protect against the prosecution test.
Fine exposure
Breaches carry an unlimited fine and the possibility of imprisonment under the regulations. Insurance cover is typically voided on any claim involving an uninspected gas appliance, so the real exposure is wider than the fine alone.
Issuing the certificate
A copy must go to existing tenants within 28 days of inspection, and new tenants must receive a copy before moving in. Email plus a retained PDF in the tenancy file is sufficient; the "in writing" requirement has been read to include email.
What it costs
- CP12 / Landlord Gas Safety Record
- Get a quote Varies with the number of appliances. Bundling with the annual boiler service in one visit is usually cheaper.
We do not publish a single fixed price; it depends on the number of gas appliances. Bundle deals from a single Gas Safe engineer are usually cheaper than separating the visits.
How to choose a vetted trade
- Use a Gas Safe registered engineer and verify their registration number, including the appliance categories they are qualified for.
- Diarise the renewal for the final 28 days before expiry to keep the anniversary date.
- Keep dated evidence of access attempts and a retained PDF of each certificate in the tenancy file.
Frequently asked questions
How often does a landlord need a gas safety check?
Once every 12 months, for every rental with a gas appliance, pipework or flue, under the Gas Safety (Installation and Use) Regulations 1998. The check produces the CP12 / Landlord Gas Safety Record. Without one in date you cannot legally let or re-let the property.
Can I renew the CP12 early without losing the date?
Yes, within the final 28 days before expiry, which preserves the original anniversary date. Renew earlier than that and the new 12-month clock starts from the inspection date, shortening your cycle. Most landlords renew in that final two-week window.
What if my tenant will not give access for the check?
You must show evidence of reasonable attempts, in writing rather than just verbal, and keep dated copies. The certificate cannot be issued without an inspection, but a documented paper trail of attempts protects you against the prosecution test if access is genuinely refused.
Sources
Editor, Sorted Property
Oliver leads Sorted Property's editorial coverage of UK home services. He researches and writes the plain-English guides that help homeowners choose between installers and trades, drawing on the standards set by bodies such as MCS, TrustMark, the Energy Saving Trust and the Property Care Association, and is clear about what to check before any work starts.
Last reviewed: 11 June 2026