A gas safety certificate is genuine only if the engineer named on it was Gas Safe registered for that work, and if the document carries every detail the law requires. Take the licence number from the engineer's ID card, check it against the Gas Safe Register's own check service, then match the same number and name to the record in your hand. In England the rules come from the Gas Safety (Installation and Use) Regulations 1998 as amended. The sections below set out what the card shows, what the record must contain, and what you can do when the two do not agree.
Which six details must a gas safety record show in England?
In England, regulation 36(3)(c) of the Gas Safety (Installation and Use) Regulations 1998 as amended lists what the record of a gas safety check must contain. A document that misses one of these details is not a compliant record, however official the layout looks.
- A description and the location of each appliance and flue that was checked
- The name, registration number and signature of the engineer who carried out the check
- The date the check was carried out
- The address of the property
- The name and address of the landlord, or of the agent acting for them
- Any safety defect found, and the action taken to put it right
Software packages print these fields in different orders, so the design of the page proves nothing. HSE calls the document a record of the gas safety check. Gas safety certificate and CP12 are everyday names for the same thing. The wider duty is set out in our guide to landlord gas safety in England.
What does a Gas Safe registered engineer's ID card show, front and back?
The front of a Gas Safe ID card shows a photograph, the registration number and an expiry date. The back lists the categories of gas work that engineer is qualified for, such as boilers, cookers or gas fires. HSE encourages you to ask to see the card before any work starts.
Other features on the card include the business registration number, the engineer's personal licence number, the company name, the start and expiry dates and a security hologram. Read the dates as well as the photograph. An expired card, or a company name that does not match the firm that sent the engineer, is a reason to pause and ask.
A card that is in date does not by itself mean the engineer may work on your appliance. Competence is shown category by category on the back. Under the 1998 Regulations in England, anyone working on gas appliances in a home must be on the register and competent for that type of gas work.
How do you check the registration number against the Gas Safe Register?
HSE sets out three ways to check whether an engineer is Gas Safe registered, all of them using the licence number taken from the ID card.
- The register's Check an Engineer service online, using the licence number from the card
- The register's freephone helpline
- A text message quoting the seven-digit licence number
Compare what comes back with the paperwork. The name and registration number printed on the gas safety record should match the card and the register entry. Regulation 3 of the 1998 Regulations requires competence and membership of the approved class for gas work in England. Regulation 3(5) adds that no person shall falsely pretend to be a member of that class.
One number carries the whole check: the engineer's registration number. It appears on the ID card, on the gas safety record and in the register entry. If those three do not agree, treat the record as unverified and raise it before any further gas work happens at the property.
Gas safety record or Benchmark service record: which document do you have?
A Benchmark checklist sits in the back of the appliance manual and records commissioning and annual servicing. It is not the record of a gas safety check that a landlord in England has to produce.
| Criterion | Gas safety record (CP12) | Benchmark service record |
|---|---|---|
| Why it exists | Records the annual gas safety check required of landlords in England under regulation 36 of the 1998 Regulations | Shows the appliance was commissioned and serviced to the manufacturer's instructions |
| Where you find it | A separate document issued and signed by the engineer after the check | Printed pages at the back of the appliance installation and user manual |
| Who it has to reach | Tenants receive a copy; the landlord keeps the record | Stays with the household as part of the appliance paperwork |
| What it affects | The landlord's legal duty for the let property | The manufacturer's warranty, which normally needs annual servicing by a registered engineer |
Work out which document you are holding before you judge it. A Benchmark page cannot carry the six details that regulation 36 requires, because it was never written for that purpose. The two visits are compared in our guide on a gas safety check and a boiler service.
What can you do if the record or the engineer does not check out?
Ask for a corrected gas safety record if the name, number, address or appliance list does not match reality. A record with the wrong property address or a missing signature does not become valid by being filed away.
A tenant who has received no record can ask the landlord in writing first. HSE also publishes form LGSR1 for reporting a property with no record of a gas safety check.
Suspected gas work by someone who is not registered can be reported to the Gas Safe Register. HSE investigates and prosecutes illegal gas work. In a statement dated 14 September 2026, HSE reported 17 convictions for illegal gas work since the start of 2025. Unqualified gas work has led to gas leaks, explosions, fires and carbon monoxide poisoning.
Several of those prosecutions involved traders who looked like a legitimate company to the householder. That is the practical reason for checking the card and the number rather than the letterhead.
When is a gas safety record due, and when must a tenant get a copy?
Each gas appliance and flue in a rented home in England needs a safety check every 12 months. A newly installed appliance is checked within 12 months of installation, then annually after that. A date more than a year old on the record tells you the next check is already due.
Existing tenants receive a copy of the record within 28 days of the check. New tenants receive a copy before they move in. The landlord keeps records until two further checks have been carried out, which HSE describes in short as keeping the record for two years.
Anyone lawfully living in the premises can ask to see the record, on request and after reasonable notice. Deadlines and proof of sending are covered in our guide on giving a tenant a copy of the gas safety certificate. If you let property in London or the surrounding counties, you can arrange a landlord gas safety certificate (CP12) with a Gas Safe registered engineer and receive the record by email.
Sources
- HSE - Check an engineer: are they Gas Safe registered?
- HSE - Gas Safe Register and the ID card
- HSE - Gas safety check records and what to keep
- legislation.gov.uk - Gas Safety (Installation and Use) Regulations 1998, regulation 36
- legislation.gov.uk - Gas Safety (Installation and Use) Regulations 1998
- GOV.UK - Private renting: your landlord's safety responsibilities
- HSE - LGSR1: details of property with no record of a gas safety check
- HSE press release - Families warned of risk to life from unregistered gas work (14 September 2026)
- Baxi - Benchmark for installers