Gas Safety Certificate London: CP12 Guide for Landlords and Agents

A Gas Safety Certificate is the official record confirming that the gas appliances, fittings and flues in a property have been inspected and are safe to use. It must be carried out by a Gas Safe registered engineer — the only engineers legally permitted to work on gas appliances in the UK. For landlords, arranging this is a legal duty under the Gas Safety (Installation and Use) Regulations 1998.

You'll often hear a Gas Safety Certificate called a CP12. The two terms mean the same thing: CP12 is the long-standing name for the Landlord Gas Safety Record, and it's the everyday shorthand used by landlords, agents and engineers. If a tenant or letting agent asks for your "CP12 certificate," they're asking for your current Gas Safety Certificate.

Any landlord letting a property with gas appliances — a boiler, gas hob, gas fire or similar — is legally required to hold a valid Gas Safety Certificate. This applies to most private rentals across London, including flats, houses and HMOs. The duty covers the appliances and flues the landlord owns or provides. Letting agents and property managers usually arrange the check on the landlord's behalf.

A Gas Safe registered engineer checks that each gas appliance operates safely and at the correct pressure, inspects flues and ventilation, tests for gas tightness, and records the results before issuing the certificate. If an appliance is found to be unsafe, the engineer advises on the action required. The check focuses on safety rather than servicing, though the two are often arranged together.

The cost depends on the number of gas appliances checked, the property type and access, and whether you bundle the check with other compliance services such as an EPC or EICR. A single-boiler flat is usually quicker than a property with several appliances. Property Motion keeps pricing transparent with no hidden micro-fees. [CONFIRM PRICE]

Landlords must arrange a gas safety check every 12 months. Once done, you must give existing tenants a copy within 28 days and provide it to new tenants before they move in. Booking a little before the 12-month deadline avoids any gap in cover, and Property Motion can help you stay ahead of renewal dates across a portfolio. (⚠ VERIFY: confirm current record-keeping and notification timeframes on gov.uk/HSE before publishing.)

Yes. Most landlords need more than one certificate, so Property Motion lets you book your Gas Safety Certificate, EPC and EICR together and manage them from one dashboard — fewer appointments, fewer suppliers to chase, one renewal view. See our complete landlord certificates guide. For business premises, see our commercial gas safety certificate guide.

Property Motion connects London landlords, agents and property managers with Gas Safe registered engineers through one booking process. Order your certificate, track the appointment, and receive your CP12 — then combine it with your other compliance certificates and let the platform help you stay on top of annual renewals.