What is a CP12?
A CP12 (short for CORGI Proforma 12) is the informal name for a Landlord Gas Safety Record — the legal document that proves every gas appliance and flue in a rented property has been checked by a Gas Safe registered engineer in the last 12 months.
It's required for every property let out on an Assured Shorthold Tenancy in the UK — houses, flats, HMOs, holiday lets and Airbnb short-lets included.
The 12-month rule (and the flexibility you didn't know about)
A CP12 must be renewed within 12 months. But since 2018, the rules let you renew up to 2 months early without losing your existing expiry date. Meaning: schedule the check in the 10–12 month window and your next expiry stays the same, avoiding "creep".
What we check
- Gas tightness test on the pipework
- Standing pressure and working pressure at each appliance
- Combustion analysis of the boiler and any gas fire
- Flue integrity and condition (visible and internal)
- Ventilation to the room
- Safe operation of all controls and safety devices
- Visual inspection of gas cooker/hob if included
2026 CP12 pricing
| Property setup | Price | Time on site |
|---|---|---|
| Boiler only (1 appliance) | £70 – £95 | 30–45 min |
| Boiler + gas hob (2 appliances) | £90 – £120 | 45–60 min |
| Boiler + hob + gas fire (3 appliances) | £110 – £140 | 1 hr |
| Boiler service + CP12 combo | £120 – £160 | 1 hr |
| HMO / multi-unit block | Discounted per unit | On quote |
What happens if you don't have one?
- • Unlimited fines under the Gas Safety (Installation and Use) Regulations 1998.
- • Up to 6 months in prison for serious or repeat breaches.
- • Your Section 21 eviction notice becomes invalid — you can't remove a tenant.
- • Landlord insurance is voided — a fire or CO incident becomes uninsured.
- • Local council can issue an improvement or prohibition notice on the property.
Landlord obligations — the full list
- Arrange an annual gas safety check by a Gas Safe registered engineer.
- Give the tenant a copy of the CP12 within 28 days of the check.
- Give any new tenant a copy before they move in.
- Keep records for at least 2 years.
- Fix anything marked "at risk" or "immediately dangerous" — the engineer will disconnect anything unsafe on the day.
Related reading
Book your CP12 — issued same day
Gas Safe registered, covering Bath, Radstock, Wells, Midsomer Norton and Somerset. Portfolio landlords welcome — block bookings discounted.