Landlord gas safety certificate (CP12): the rules and renewal

What 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 two-month renewal window

Since the 2018 amendment to the regulations, the HSE says the annual check can be carried out up to 2 months before it is due while keeping the original deadline date, as if it had been done exactly 12 months after the previous check. Renew earlier than that and the new 12-month clock starts from the inspection date, shortening the cycle.

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: a notice left after a missed visit and a letter explaining that the check is a legal requirement, and its inspectors look for at least three attempts. Keep dated copies. The CP12 cannot be issued without an inspection, but documented attempts protect against the prosecution test.

Penalties

The HSE treats landlord gas safety as a high priority and says a breach could result in a substantial fine and/or a custodial sentence. Check your landlord insurance policy wording too, as cover conditions vary between insurers.

Issuing the certificate

A copy must go to existing tenants within 28 days of the check, and new tenants must receive a copy before they move in. The HSE allows the record to be sent electronically, such as by email, provided the tenant is happy with that and can access it. Keep a retained PDF in the tenancy file.

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We do not publish a single fixed price; it depends on the number of gas appliances.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.