CP12 Landlord Gas Safety Record: The Complete Guide for 2025
A CP12 is the document most gas engineers produce more than any other. Yet misconceptions about what it must contain, who can issue it, and what happens when it’s missing still cause serious problems for landlords and engineers alike. This guide covers everything you need to know.
What is a CP12?
CP12 is the form reference number (from Gas Industry Unsafe Situations Procedure) for a Landlord Gas Safety Record. It confirms that a Gas Safe registered engineer has inspected the gas appliances and installation in a rented property and found them safe.
The term “CP12” comes from the old Corgi certification era but has stuck as the colloquial name. Officially, Gas Safe Register refers to it as a Landlord Gas Safety Record or LGSR.
Who Needs One?
Any landlord renting residential property in the UK that has gas appliances fitted — boilers, gas fires, gas cookers, gas water heaters — must have a valid CP12 in place. This includes:
- Private landlords renting a single room
- Buy-to-let landlords
- Housing associations and social landlords
- Landlords renting to Airbnb or short-term tenants
Owner-occupiers are not legally required to have a CP12, though a Gas Safe service certificate is strongly advisable.
What Must a CP12 Include?
The Gas Safety (Installation and Use) Regulations 1998 specify the exact contents. A valid CP12 must state:
- The address of the property inspected
- The date of inspection
- The name and Gas Safe registration number of the engineer
- A description of each appliance or flue inspected
- The location of each appliance
- Any defects identified and the action taken
- Confirmation of whether each appliance is safe to use
- The signature of the engineer
Missing any of these elements technically invalidates the document. If you’re generating CP12s by hand or using a generic PDF template, check every record carefully.
How Often is a CP12 Required?
Landlords must arrange an inspection at least every 12 months. The engineer who carries out the work must be Gas Safe registered for the appliance type — for example, a CMDDA1-qualified engineer for domestic natural gas appliances.
The inspection can be carried out up to two months before the expiry date without losing the anniversary date for the following year. So a certificate expiring on 31 March can be renewed from 1 February onwards and will still run to 31 March the following year.
Giving a Copy to Tenants
Landlords must give existing tenants a copy of the new certificate within 28 days of the inspection. New tenants must receive a copy before they move in.
Landlords must keep copies of all records for at least two years.
What Are the Penalties?
Failing to comply with the Gas Safety Regulations is a criminal offence. The Health and Safety Executive (HSE) can prosecute landlords who:
- Do not arrange annual gas safety checks
- Fail to use a Gas Safe registered engineer
- Do not provide tenants with a copy of the certificate
Penalties include unlimited fines and up to two years in prison. In practice, the HSE more commonly issues improvement notices and prohibition notices — but prosecution does happen, particularly following an incident.
Common Reasons a CP12 Gets Marked “At Risk” or “Immediately Dangerous”
Not every inspection results in a clean pass. Engineers may need to mark appliances as:
- Immediately Dangerous (ID): Must be taken out of use immediately
- At Risk (AR): Should be taken out of use; risk is not immediate but significant
- Not to Current Standards (NCS): Does not meet current standards but is not dangerous
If an appliance is marked ID or AR and the tenant refuses to allow the engineer to disconnect it, the engineer must document this and report it. They cannot simply sign off a dangerous appliance to keep a landlord happy.
How Heatflow Handles CP12s
Heatflow generates compliant CP12s directly from job data. As you complete the inspection — logging appliances, entering readings, recording defects — the certificate populates in real time. When you’re done, you send the signed PDF directly to the landlord from the app.
No manual data entry after the job. No chasing invoices separately. The 12-month renewal reminder goes to the landlord automatically, which means returning work comes to you rather than drifting to whoever answers the phone first.