What is a CP12?

“CP12” is the old form code that stuck. The document is now officially called the Landlord Gas Safety Record, but almost everyone in the trade still calls it a CP12, and landlords often call it a “gas safety certificate”. They all mean the same thing: the record of an annual gas safety check on a rented property.

What does a CP12 actually record?

The record is the engineer's written account of what was checked and what was found. During the visit, a Gas Safe registered engineer inspects every gas appliance, fitting and flue that the landlord is responsible for, appliance by appliance, and records the results. A completed CP12 typically lists:

• Each appliance and flue checked, with make, model and location
• Whether each one passed, and any defects found
• Safety checks: gas tightness, burner pressure or heat input, flue performance, ventilation and safety devices
• The date of the check and the next check due date
• The engineer's name, Gas Safe licence number and signature

Each appliance gets its own line and its own verdict. That matters more than it sounds. A property can be broadly fine while one appliance is flagged with a defect, and the record is what tells the landlord which one, what the problem is, and what the engineer did about it on the day.

Who needs a CP12?

Landlords do. Anyone letting a property with gas appliances has a legal duty under the Gas Safety (Installation and Use) Regulations 1998 to have this check carried out every 12 months. That covers ordinary tenancies, rooms let in a shared house, HMOs and rented holiday accommodation; the duty follows the letting, not the length of the stay. The formal trigger is letting under a lease or licence shorter than seven years, which in practice sweeps in nearly every residential letting.

Homeowners aren't legally required to have an annual check, though many arrange the same inspection for peace of mind, recorded on a homeowner gas safety record. It becomes a legal duty the day you start letting the property out.

Who can issue one?

Only a Gas Safe registered engineer who carried out the check, and only for the appliance types on their licence. The document has no authority of its own; a blank CP12 form is just paper. What makes the record valid is the registered engineer standing behind it, which is why no template or “free CP12 generator” can produce one. Before the check starts, ask to see the engineer's Gas Safe ID card and glance at the back, where their qualified appliance types are listed.

What happens during the check?

As for time, reckon on roughly 20 to 30 minutes per appliance, so a one-boiler flat is a short visit while a house with a boiler, hob and gas fire takes a fair chunk of the morning. The engineer has to reach and run every appliance to test it, so agreed access, appliances that aren't boxed in behind stored belongings, and credit on a prepayment meter are what keep the visit to one trip instead of two.

What doesn't a CP12 cover?

A boiler service, for one. The gas safety check is an inspection with a verdict; a service is maintenance, with the appliance opened up, cleaned and adjusted to the manufacturer's instructions. An appliance can pass its safety check and still be years overdue a service, which is why landlords carry a separate ongoing duty to keep appliances maintained, and why many book the service and the check as a single visit.

The record has edges, too. It covers the appliances and flues the landlord provides, so a cooker the tenant owns is usually the tenant's responsibility, though the connecting pipework and any flue it uses typically stay with the landlord and stay on the check. Electrics are a different regime entirely: rented homes in England need an EICR at least every five years under the 2020 electrical safety rules, issued by a qualified electrician rather than a gas engineer. And since October 2022, landlords in England must also fit a carbon monoxide alarm in any room used as living accommodation with a fixed combustion appliance, gas cookers excepted. None of those duties lives on the CP12, but they all get asked for at the same moments, so the sensible habit is one file that holds the lot.

What do you do with the record once it's issued?

Three things, and they're all deadlines. Give each existing tenant a copy within 28 days of the check. Give any new tenant a copy before they move in. Keep the record for at least two years, though in practice a full history is worth keeping for the life of the property, because solicitors, councils and insurers all ask for old records at the least convenient moments.

The handover is where paper systems fray. The check happens on time, then the record sits in a van waiting to be typed up, posted and filed. Engineers using Manifold complete the CP12 on their phone at the property and send it the moment it's signed, so the 28-day duty is handled on the doorstep, and the landlord's copy is findable in seconds a year later when nobody remembers which drawer it went in.