What is a CP12?
"CP12" is the everyday name for a Landlord Gas Safety Record. It's a legally required certificate confirming that the gas appliances, pipework and flues in a rental property have been inspected by a Gas Safe registered engineer within the last 12 months. The number comes from the old CORGI form number; Gas Safe inherited it in 2009 and the name stuck.
Who needs one?
- Landlords of any property let out, including HMOs, holiday lets and short-term rentals.
- Letting agents managing properties on a landlord's behalf.
- Housing associations and councils for their stock.
Owner-occupiers don't legally need one — but most homeowners get a Gas Safety Check before selling.
What does the engineer check?
- Every gas appliance (boiler, hob, fire) — operating pressure, safety devices, combustion ratio.
- Flues and chimneys — flue flow, spillage test, condition.
- Pipework — visual inspection and a tightness test.
- Ventilation — adequate supply for each appliance.
What does a CP12 cost in 2026?
Typical UK pricing: £60–£90 for one appliance, £75–£120 for two, then £20–£30 per extra appliance. London and combined gas + EICR jobs sit higher.
How often?
Every 12 months. The certificate must be issued to the tenant within 28 days of the check (or before move-in for new tenancies). Landlords must keep records for 2 years.
For Gas Safe engineers: issuing CP12s cleanly
The legal minimum is a paper or PDF record with the appliance details, defects, results and your Gas Safe number. In practice, landlords want:
- A PDF emailed within an hour of the visit.
- Photos of any defects attached.
- A re-test reminder 11 months later.
Job Snapper handles all three — see Job Snapper for gas engineers.