CP12 Certificate Explained: What Landlords Must Provide

A CP12 certificate is the usual name for a landlord gas safety record. It confirms that gas appliances and relevant flues in a rented property have been checked by a Gas Safe registered engineer and are safe to use at the time of inspection. Understanding the process helps landlords organise access, keep accurate records and communicate clearly with tenants.

What a CP12 certificate covers

A CP12 is issued after a registered engineer completes the required gas safety checks on appliances and flues provided for tenants. The inspection is designed to identify issues such as unsafe combustion, poor ventilation, gas leaks and problems with the flue or appliance installation.

Typically, the inspection may include a gas boiler, gas hob or cooker, gas fire and any other gas appliance supplied by the landlord. Appliances belonging to a tenant are generally not part of the landlord’s inspection, although the engineer may need to consider the installation or flue where it affects overall safety.

The record usually identifies each appliance, its location, the checks carried out, any defects found and the engineer’s Gas Safe registration details. Landlords should make sure the appliance list is complete, particularly after replacing a boiler, adding a gas fire or carrying out refurbishment.

How often is a gas safety check needed?

Landlords normally arrange a gas safety check every 12 months. The inspection must be completed by a Gas Safe registered engineer, and the timing should be managed carefully so there is no gap between certificates.

For a new tenancy, the relevant gas safety record should normally be provided before the tenant moves in. For an existing tenant, a copy is typically supplied within 28 days of the check. Landlords commonly retain gas safety records for at least two years, while also keeping the current record available for the tenant.

Before the engineer visits

Good preparation makes the appointment more efficient and reduces the risk of an appliance being missed. Landlords and agents should agree access arrangements with the tenant in advance, especially where the boiler, gas meter or flue is inside a cupboard or another restricted area.

• Confirm access to every room containing a gas appliance or relevant flue.

• Prepare a list of landlord-provided appliances, including the boiler, hob and fire.

• Have previous gas safety records available where possible.

• Note the boiler make and model, along with any known faults or recent repairs.

• Send tenants clear appointment details and explain that appliances may need to be operated during the check.

Tenants should not be expected to arrange access at short notice without suitable communication. If the engineer cannot reach an appliance, the record may not cover it, so arranging a follow-up visit could be necessary.

What happens if an appliance is unsafe?

If an engineer identifies a problem, they will explain the finding and record the relevant classification. An appliance marked At Risk has a fault that could make it unsafe under certain conditions. The engineer will usually advise that it is not used until the problem is resolved, and may isolate it in line with industry procedures and the circumstances of the visit.

An Immediately Dangerous appliance presents a serious and immediate danger if operated or left connected. The engineer will explain the action required, which may include disconnecting or isolating the appliance and placing an appropriate warning notice. Landlords should arrange repairs or replacement promptly through a suitably qualified professional and should not allow tenants to use an appliance that has been labelled unsafe.

A CP12 is not simply a pass that removes all future responsibility. It records the condition found on the inspection date, so landlords should respond to defects, retain evidence of completed work and provide updated information when appropriate.

Gas safety check and boiler service

A landlord gas safety check and a boiler service are separate appointments with different purposes. The CP12 inspection focuses on gas safety requirements for relevant appliances and flues, while a boiler service is a more detailed maintenance visit intended to assess the boiler’s condition, performance and components.

A boiler service may include cleaning, checking seals and controls, testing operation and identifying wear that could lead to a breakdown. It does not replace the annual CP12 check, and a CP12 inspection does not necessarily include every maintenance task covered by a full boiler service.

Many landlords choose to arrange both during the same visit, where suitable, because it creates a clearer maintenance routine and can help identify developing boiler problems early. Always confirm with the engineer what each appointment includes and ensure the person carrying out the gas work is Gas Safe registered.

After the visit

Once the inspection is complete, check that the certificate identifies the correct property, appliances and inspection date. Provide the record to the tenant in the expected timescale, retain a copy with the property documents and share it with a managing agent or incoming tenant where relevant.

• Save the certificate securely in both digital and, where useful, paper records.

• Record any defects, repairs or appliance restrictions and keep related invoices or reports.

• Set a reminder for the next annual gas safety check.

• Update the appliance list after replacements, removals or major works.

For further guidance, see our landlord gas safety certificates service and our boiler servicing page. These can help you plan the right checks for your property without confusing a safety record with routine maintenance.

Arrange your next check with confidence

Keeping CP12 records organised supports clear communication with tenants and demonstrates a responsible approach to property management. When booking, use a Gas Safe registered engineer and ask what will be inspected, what paperwork you will receive and whether any follow-up work is recommended.

For help arranging a landlord gas safety check or boiler service, contact 7 Day Plumbing Services Ltd on 07896487603.