Home › Articles › Gas Safety Certificate (CP12)
Gas Safety Certificate (CP12): A Landlord's Guide & Cost
Updated 7 August 2026
If your rental has any gas appliances, the annual Gas Safety Record — still widely called a CP12 — is one of your most important legal duties. Miss it and it's a criminal matter, not a civil one. This guide explains exactly what a CP12 is, what's checked, who can issue one, how often you need it, what it costs, how to tell a valid certificate from an invalid one, and the rules on giving it to tenants. It sits within the wider landlord compliance checklist.
In short: A CP12 is a landlord's gas safety certificate — officially the Landlord Gas Safety Record. It's issued by a Gas Safe registered engineer after they check that the gas appliances, flues and pipework in a rental property are safe, and it must be renewed every 12 months. "CP12" and "gas safety certificate" mean the same thing.
On this page
What is a CP12?
A CP12 is the common name for the Landlord Gas Safety Record — the certificate a Gas Safe registered engineer issues after confirming that the gas appliances, flues and pipework in a property are safe to use. The name "CP12" comes from the old CORGI proforma number; CORGI was replaced by the Gas Safe Register in 2009, and the legal document is now officially the Landlord Gas Safety Record — but "CP12" and "gas safety certificate" have stuck and mean the same thing. It's required under the Gas Safety (Installation and Use) Regulations 1998.
What's checked and what's on it
During the check the engineer inspects every gas appliance, flue and the gas pipework, testing that appliances burn correctly, that flues carry fumes safely away, and that there are no gas leaks. A valid record will show:
- The property address and the landlord's or agent's details.
- The engineer's name, signature and Gas Safe licence number.
- Each appliance and flue checked, its location, make and model.
- The results of the safety checks and any defects found.
- Any appliance classified "At Risk" or "Immediately Dangerous", and the action taken.
- The date of the check and the date the next one is due.
Who can issue a CP12?
Only a Gas Safe registered engineer whose registration covers the appliance types in your property can carry out the check and issue the record. Every registered engineer carries a Gas Safe ID card showing what they're qualified to work on, and you can confirm any engineer's registration free on the Gas Safe Register. A certificate from anyone not on the register is not valid.
How often you need one
Every 12 months. Helpfully, the check can be done up to 2 months before the current record expires while keeping the same anniversary date — so booking early never shortens your certificate. For example, a record expiring 1 December can be renewed any time from 1 October and still keep its 1 December renewal date. That two-month window is the safest time to book, because it builds in slack if an engineer is hard to get.
Serving it to tenants — the rules
- Give a copy to new tenants before they move in.
- Give it to existing tenants within 28 days of the check.
- Keep records for at least 2 years.
For assured shorthold tenancies, failing to provide a valid gas safety record can also affect your ability to serve a valid Section 21 notice, so this isn't just a safety formality.
How to check a CP12 is valid
If you've inherited a property or use a managing agent, check the record actually stacks up: it should list the correct address, show a Gas Safe licence number you can verify, cover every gas appliance in the property (not just the boiler), be dated within the last 12 months, and record no outstanding "At Risk" or "Immediately Dangerous" items left unresolved. A certificate that's missing appliances or issued by an unregistered fitter won't protect you.
What does a CP12 cost?
Costs vary by region, engineer and number of appliances, but as a guide a landlord gas safety check typically costs around £60–£90 for a property with one or two appliances, with a little more per extra appliance. Bundling the check with an annual boiler service is often better value. Remember the CP12 and a boiler service are different things — the CP12 is a safety check and record, the service is maintenance — though many engineers do both in one visit.
The real risk isn't the check — it's the date. Failing to hold a valid record can mean an unlimited fine and, in the worst cases, prosecution. JRM Compliance reads your certificate dates and reminds you well ahead, so the CP12 gets booked before expiry, every year, across every property.
Penalties for getting it wrong
The gas safety duties are enforced by the Health and Safety Executive (HSE), and breaches are treated seriously because faulty gas kills. Penalties for not holding a valid record, or for unsafe appliances, can include unlimited fines and, in serious cases, imprisonment. Add the risk to a Section 21 possession claim and the cost of getting it wrong dwarfs the price of the annual check.
Frequently asked questions
What is a CP12 certificate?
A CP12 is the common name for the Landlord Gas Safety Record — the certificate a Gas Safe registered engineer issues after checking the gas appliances, flues and pipework in a rental are safe. "CP12" comes from the old CORGI proforma number; the legal document is now the Landlord Gas Safety Record, but the CP12 name has stuck.
Is a CP12 the same as a gas safety certificate?
Yes — "CP12", "gas safety certificate", "landlord gas safety record" and "gas safety record" all mean the same annual document. It is not the same as a boiler service, which is separate maintenance.
How often does a landlord need a gas safety certificate?
Every 12 months. A Gas Safe registered engineer must check all gas appliances, flues and pipework annually. The check can be done up to 2 months before the current record expires while keeping the same anniversary date.
How much does a CP12 cost?
It varies by region and number of appliances, but a landlord gas safety check typically costs around £60–£90 for one or two appliances, with a small charge per extra appliance. Combining it with a boiler service can be more economical.
Who can issue a CP12?
Only a Gas Safe registered engineer whose registration covers the appliance types being checked. Confirm registration on the Gas Safe Register — their licence card shows the work they are qualified to do.
Do I need a CP12 if the property has no gas?
No. A gas safety record is only required where there are gas appliances, flues or pipework. A fully electric property doesn't need a CP12, but still needs its 5-yearly EICR and other standard compliance.
Read the full UK Landlord Compliance Checklist → · See how JRM tracks it → · Ask us a question →
General guidance for landlords in England, not legal advice. Costs are indicative and vary by property, region and provider. Always check the current position on GOV.UK, the HSE or with a qualified adviser before acting.