Boiler Service vs Gas Safety Certificate: The Difference

A **Gas Safety Certificate — the CP12** — is a safety inspection required by law. A Gas Safe registered engineer checks every gas appliance, flue and pipework in the property to confirm it is safe to use.

• **Legally required:** yes, annually, for every rented property with a gas appliance
• **Governed by:** the Gas Safety (Installation and Use) Regulations 1998
• **Covers:** all gas appliances, flues, pipework and the meter
• **Produces:** a certificate you must give your tenant within 28 days, and keep for two years
• **Cost:** from £60 inc VAT

It answers one question: is this safe? It is not a maintenance visit, and it will not make a struggling boiler work better.

A **boiler service** is maintenance. The engineer cleans components, checks and adjusts combustion, inspects seals and the heat exchanger, and confirms the appliance is running to the manufacturer's specification.

• **Legally required:** no
• **Usually required by:** your boiler's manufacturer warranty
• **Covers:** one appliance, in depth
• **Produces:** a service record, not a safety certificate
• **Cost:** £99.99 inc VAT

Most manufacturer warranties require an annual service by a Gas Safe registered engineer, documented. Miss it and a warranty claim on an expensive component can be refused — which is where the real cost of skipping it shows up.

This is the misunderstanding worth clearing up.

A CP12 does not service your boiler. The engineer checks it is safe — combustion is within range, the flue is clear, there is no leak. If it is dirty, inefficient or heading for a failure that is not yet a safety issue, that is outside the scope.

A boiler service does not certify your other gas appliances. If you have a gas hob and a gas fire as well, a boiler service covers neither. Your legal obligation is to all of them.

So a landlord who books only a service is **not legally compliant**. A landlord who books only a CP12 is compliant, but may be **invalidating their warranty** and running a boiler nobody has maintained.

You must have a CP12. Annually, without exception, if there is a gas appliance in the property. This is not optional and not a judgement call.

You probably want a service if:

• The boiler is still under manufacturer warranty — almost always a condition of it
• The boiler is more than five years old and has never been serviced
• Tenants have reported poor heating or hot water
• You want to avoid a mid-winter breakdown and an emergency call-out

If the boiler is new, under warranty, and was serviced ten months ago, the CP12 alone is fine this year.

Both jobs need a Gas Safe registered engineer and both need access to the property, so doing them separately means paying twice for attendance and arranging tenant access twice.

Booked together: **CP12 + full boiler service for £129.99 inc VAT** — against £159.99 separately.

One visit, one access arrangement with your tenant, and you leave with both the certificate the law requires and the service record your warranty requires. All prices include VAT, with the certificate issued the same day.

We cover all 32 London boroughs and the M25 corridor. Book online or call 07426 409342.