Annual checks, Gas Safe engineers, CP12 certificates, tenant service obligations, and the penalties for getting it wrong. Updated for 2026.
A gas safety certificate — formally known as a Landlord Gas Safety Record and sometimes called a CP12 — is a document issued by a Gas Safe registered engineer after completing an annual inspection of all gas appliances and pipework at your rental property.
The certificate confirms that all gas appliances provided by you as the landlord are safe to use. It records the results of each test: whether the appliance passed, any defects found, and the engineer's Gas Safe registration number.
The legal requirement for annual gas safety checks is set out in the Gas Safety (Installation and Use) Regulations 1998. It applies to all private landlords — including HMO landlords — letting residential property in England, Scotland, and Wales.
The engineer checks all gas appliances provided by you as the landlord. This typically includes:
You must give a copy of the certificate to tenants. The timing depends on whether they are existing or new tenants:
Within 28 days of the check being carried out. Email is acceptable — no requirement for a hard copy.
Before they move in — not within 28 days of the check. The certificate must be valid at tenancy start.
You must keep a copy for at least 2 years. If asked by HSE inspectors, you must be able to produce records for the current and previous certificates.
You can have the annual check carried out up to 2 months before the current certificate expires and the new expiry date will be calculated from the old expiry date — not from the date of the new check.
If you book more than 2 months early, the new expiry will be 12 months from the date of the check — you lose the protected anniversary date.
Failure to carry out annual gas safety checks is a criminal offence under the Gas Safety (Installation and Use) Regulations 1998. It is not a civil penalty — it is prosecuted by the Health and Safety Executive (HSE).
In practice, HSE prosecutions for landlords without a gas safety certificate typically result in fines between £5,000 and £20,000 plus costs. Ignorance of the requirement is not accepted as a defence.
A gas safety certificate (formally a Landlord Gas Safety Record, sometimes called a CP12) is a document issued by a Gas Safe registered engineer after carrying out an annual inspection of all gas appliances and pipework at your rental property. It confirms the appliances are safe to use and records the results of each safety check.
Every 12 months. The check must be carried out by a Gas Safe registered engineer. You can have the check done up to 2 months before the current certificate expires and still keep the same renewal date — this is the "2-month window" rule.
Only an engineer registered on the Gas Safe Register. You can verify a registration at gassaferegister.co.uk. The engineer must be registered for the type of appliance being checked — domestic gas is a separate category from commercial. Always check the engineer's Gas Safe ID card before they start work.
Existing tenants: within 28 days of the check being carried out. New tenants: before they move in — not within 28 days, but before the tenancy starts. You must also keep a copy for at least 2 years.
All gas appliances provided by you as the landlord: boilers, gas hobs, gas fires, gas water heaters, and any gas supply pipework. Appliances owned by the tenant (e.g. a tenant's own gas cooker) are their responsibility, not yours — though the gas pipework feeding them remains your responsibility.
The engineer will classify it as Immediately Dangerous (ID) or At Risk (AR). ID appliances must be disconnected immediately. AR appliances must be repaired before use. In both cases, the engineer will issue a defect notice and you must not allow the appliance to be used until it is repaired and re-inspected.
Non-compliance is a criminal offence under the Gas Safety (Installation and Use) Regulations 1998. Penalties include an unlimited fine and up to 6 months imprisonment. In practice, HSE prosecutions have resulted in fines of £5,000–£20,000 and suspended sentences. A gas explosion caused by a poorly maintained appliance has resulted in manslaughter charges.
Yes. If your certificate expires on 1 March, you can have the check done any time from 1 January onwards and your new expiry date will still be 1 March the following year — not 2 months earlier. This prevents certificates gradually drifting earlier each year. The rule only applies if you book within 2 months of expiry, not earlier.
No legal obligation when the property is void — but good practice to have one ready before new tenants move in. The certificate must be valid at tenancy start.
The same rules apply. All gas appliances provided by the landlord must be checked annually and all tenants must receive the certificate within 28 days. For a house of multiple occupation, this means every named tenant on every room.
LetSense tracks gas safety certificates for your entire portfolio — with automatic reminders at 90, 60, and 30 days before expiry. Upload your cert and the expiry date is extracted automatically.