Gas Safety Certificate London — The Complete 2026 Guide for Landlords

The gas safety certificate — formally known as a CP12 — is the one compliance certificate that almost every private landlord has heard of. It is also, in our experience carrying out gas safety inspections across London, the one most likely to be renewed late or let lapse.

The consequences of a lapsed gas safety certificate are among the most serious in the entire landlord compliance framework. This guide covers everything you need to know — what is inspected, what it costs, how often you need it, and what the implications of non-compliance are in 2026.

What the law requires

Under the Gas Safety (Installation and Use) Regulations 1998, every private landlord must arrange an annual gas safety inspection of all gas appliances, flues, and associated pipework in their rental properties. The inspection must be carried out by an engineer registered with the Gas Safe Register — the official UK body replacing CORGI that took over gas safety regulation in 2009.

The engineer completes a Gas Safety Record (the CP12) documenting the results of the inspection for every appliance and fitting checked. You must keep a copy of this record for at least two years and provide a copy to your tenant:

• New tenancies: before the tenant moves in
• Existing tenancies: within 28 days of each annual inspection

Providing it digitally (emailing a PDF) is perfectly valid. The key is that you can demonstrate it was provided and when.

What the gas safety inspection covers

A Gas Safe registered engineer arriving at your property will inspect and test every gas appliance, flue, and fitting in the property. This includes:

Boiler: Safety devices, operating pressure, flue integrity, combustion analysis, heat exchanger condition, controls and timers, expansion vessel, and overall safe operation. If the property has a boiler, this is a significant portion of the inspection.

Gas hob and oven: Flame stability, ignition, burner condition, and ventilation.

Gas fire (if present): Flue integrity, flame pattern, safety shut-off, and ventilation.

Gas pipework: Checked for soundness (no leaks) using pressure testing. The pipework from the meter to each appliance is included.

Meter and emergency control valve: Checked for accessibility and correct operation.

For each item inspected, the engineer records whether it is satisfactory (S), not to current standards (N), or at risk (AR). An At Risk finding means the appliance is dangerous and should not be used — the engineer will advise the landlord or tenant to stop using it immediately and arrange repair or replacement.

Our pricing structure — a note on boilers

A point that confuses many landlords: a boiler is not counted as a standard gas appliance in our pricing.

Our pricing tiers:

• Up to 2 appliances (excl. boiler): £64.99 — covers gas hob, gas oven, gas fire, and any other gas fitting. Does not include the boiler.
• 3 appliances (excl. boiler): £74.99 — covers up to 3 gas appliances, excluding the boiler.
• Boiler check + service: £84.99 — includes a full boiler inspection and service alongside any other gas appliances in the property.

If your property has a boiler, select the boiler check + service option. A boiler service alongside the annual gas safety inspection is good practice and extends boiler life — and at £84.99, it represents excellent value compared to booking them separately.

What a 'satisfactory' vs 'unsatisfactory' result means

A satisfactory gas safety certificate means every appliance and fitting inspected is operating safely and to the required standard. You should file this, provide it to the tenant, and set a reminder to book the next inspection within 12 months.

An unsatisfactory result means one or more appliances or fittings have been found At Risk or Not to Current Standards. This does not automatically mean your tenant is in immediate danger — but it does mean you must take action promptly.

For an At Risk (AR) finding, the engineer will advise the occupier not to use the appliance and will usually issue a Gas Emergency Warning Notice or disconnect the appliance. You must arrange repair or replacement immediately.

For a Not to Current Standards (N) finding, the appliance is not dangerous but does not meet current regulations. You should arrange for the issue to be rectified and have the appliance re-inspected.

The 2-month early renewal rule

The gas safety regulations allow you to have your annual inspection carried out up to 2 months before the existing certificate expires and still have the new certificate run from the original anniversary date. This is sometimes called the 2-month window, and it is extremely useful for landlords who want to avoid their renewal date creeping through the year.

For example: if your current certificate expires on 1 December 2026 and you have the next inspection done on 15 October 2026, the new certificate will run until 1 December 2027 — not from 15 October 2026. You retain the original renewal date while having the flexibility to book slightly early.

This rule makes it straightforward to batch renewals for multiple properties and to always ensure you have a valid certificate in place without scrambling at the last minute.

The implications of a lapsed certificate in 2026

The consequences of allowing your gas safety certificate to lapse have always been severe. In 2026, with the Renters' Rights Act in force and the PRS Database launching in December, they are more consequential than ever.

Criminal liability. Failure to maintain a valid gas safety certificate is a criminal offence under the Gas Safety Regulations 1998. It carries an unlimited fine and up to two years' imprisonment. There is no minimum portfolio size — a landlord with one property is just as liable as one with a hundred.

Civil liability. If a gas incident occurs at a property without a current valid certificate, your exposure to civil claims is significant. Insurers may also challenge claims arising from incidents at unlicensed properties.

Loss of Section 8 possession rights. While a lapsed gas safety certificate does not automatically invalidate a Section 8 notice in the same way it invalidated a Section 21 notice, a well-advised tenant's legal representative will raise compliance failures in any contested possession hearing. A court can take non-compliance into account when exercising discretion on possession.

PRS Database registration block. The PRS Database, launching from 15 December 2026, requires landlords to provide their compliance certificate references as part of registration. A landlord without a valid gas safety certificate cannot demonstrate compliance during registration and will be visible as non-compliant in the database.

HMO licence breach. For HMO landlords, a valid annual gas safety certificate is a standard licence condition. An expired certificate is a breach of the licence, giving the council grounds to revoke it.

How to ensure you never miss a renewal

The most reliable system is the simplest: at the time of each inspection, book the next one for 10 months hence. This gives you a 2-month buffer before the certificate expires and means the renewal is in your diary before you walk out of the property.

If you manage multiple properties, consider keeping a spreadsheet with every certificate type, the property address, and the expiry date. A monthly check of that spreadsheet on the first of each month identifies any renewals due in the next 60 days.

Alternatively, My Landlord Certificate keeps your booking history — if you have had a gas safety inspection with us before, we can remind you when the next renewal is due.

Commercial properties — the CP42

If you own commercial premises with gas appliances — a restaurant, office, or retail unit — the annual inspection produces a CP42 rather than a CP12. The CP42 covers commercial gas appliances and pipework and is required under the same legislation. Our commercial gas safety CP42 pricing starts from £159.99 for one appliance.

Book your gas safety certificate online

We carry out gas safety inspections across all 33 London boroughs with next-day appointments. Prices are fixed — no hidden charges, no call-out fee.

Book a Gas Safety Certificate — from £64.99. Certificate emailed within 24 hours of inspection.

Call 020 3996 1070 or WhatsApp +44 7344 617792 if you have questions about which tier is right for your property.

Frequently Asked Questions