Who can issue a CP12?

Only a Gas Safe registered engineer. Always check the ID card and the register at gassaferegister.co.uk.

How much does it cost?

Typically £60–£120 for a single boiler property, more for HMOs with multiple appliances.

Do I need one if the property is all-electric?

No — if there is no gas supply, no CP12 is required.

Yes, up to 60 days before expiry without losing time on the new certificate.

What if my tenant blocks access?

Document at least three written attempts with dates. Landvale generates the required evidence log automatically.

Does the engineer test the tenant's own appliances?

Only landlord-supplied appliances are legally in scope, but Gas Safe engineers will typically flag tenant-owned appliances that look unsafe.

How long do I have to keep old certificates?

Two years minimum. Landvale stores them indefinitely by default.

What is a CD10 or LGSR?

Different names for the same document — the Landlord Gas Safety Record.

Does a CP12 cover the boiler service?

No — a CP12 is a safety inspection, not a service. Book the service separately.

Certificates

Gas Safety Certificate (CP12): Everything UK Landlords Need to Know

The Gas Safety Certificate (CP12) is the single most important document for UK landlords. Here's who needs one, how often it renews, what happens if you miss it, and how to automate the renewal cycle.

The Landvale Team·Updated 1 July 2026·9 min read

Gas Safety Certificate (CP12): Everything UK Landlords Need to Know

Key takeaways

Every rented property with a gas appliance needs an annual CP12.

The engineer must be Gas Safe registered — not just 'CORGI' or 'qualified'.

You must give a copy to the tenant within 28 days, and before any new tenancy begins.

A missing CP12 invalidates Section 21 and carries unlimited fines.

Landvale tracks CP12 expiries and books engineers automatically.

What is a Gas Safety Certificate?

The Gas Safety (Installation and Use) Regulations 1998 require every landlord to have all gas appliances, pipework and flues checked annually by a Gas Safe registered engineer.

The result is a Landlord Gas Safety Record (LGSR) — the document most people call a CP12.

Who needs a CP12?

You need one if you rent out a property that has any of the following:

•Gas boiler or combi

•Gas hob or cooker

•Gas fire, back boiler or heater

•Any gas pipework, meter or flue serving the tenant's living area

Renewal cycle and 28-day rule

The CP12 is valid for 12 months. You can renew up to 60 days early without shortening the new certificate. A copy must be given to the tenant within 28 days of the inspection, and to any new tenant before they move in.

What happens if you miss it

No CP12 = no Section 21. On top of that, the HSE can prosecute for unlimited fines and — in extreme cases — six months' imprisonment.

How Landvale automates it

Upload the last CP12, and Landvale reads the expiry date, schedules a 60-day reminder, surfaces Gas Safe engineers in your postcode, drafts the tenant access request, and files the returned certificate with a tamper-evident audit log.

Pillar guide

The Complete UK Landlord Compliance Guide

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