Gas safety certificates for rented homes: a letting agent's guide to the CP12 rules

A landlord must have every gas appliance and flue they provide checked every year by a Gas Safe registered engineer, and give tenants a copy of the record. The record is often called a CP12 or landlord gas safety certificate.

For a letting agent, the risk is not the check itself. It is the renewal that slips, the copy that never reached the tenant, and the access problem nobody wrote down. This guide covers the rules and how agencies keep on top of them. Checked against HSE and gov.uk on 17 September 2026.

At a glance

What has to be checked

The annual check covers gas appliances and flues the landlord owns and provides for tenants to use, permanent or portable. The landlord must also keep gas pipework, appliances and flues maintained in a safe condition, and have them installed and maintained by a Gas Safe registered engineer.

What the record must include

The gas safety record must show:

• each appliance or flue checked, and where it is
• the engineer's name, registration number and signature
• the date of the check
• the property address
• the landlord's name and address (or their agent's, where appropriate)
• any safety defect found and the action taken

A record with a defect listed is not a clean bill of health. If an engineer finds an appliance unsafe, it must not be used until the defect is fixed.

Copies for tenants

• Existing tenants: a copy within 28 days of the check.
• New tenants: a copy before they move in.

Keep proof of when and how each copy was given. If a tenant later says they never received one, a dated email or portal record is far better than memory.

Renewing early without losing the date

Since 2018, a check can be done up to two months before it is due while keeping the original deadline date, so a property does not drift earlier every year.

To rely on this, keep the records until two further gas safety checks have been done, so you can show the timing was met. In any case, records must be kept for at least two years.

When a tenant will not give access

The landlord must take all reasonable steps to get the check done. HSE's guidance is practical:

1. Leave a notice saying an attempt was made, with your contact details.
2. Write to the tenant explaining the check is a legal requirement for their safety.
3. Keep repeated attempts going, and keep a record of all correspondence.

HSE inspectors look for repeated attempts. Whether the steps were reasonable is ultimately for a court to decide, so the paper trail matters.

Smoke and carbon monoxide alarms

Since 1 October 2022, landlords in England must:

• have at least one smoke alarm on each storey where there is a room used as living accommodation
• have a carbon monoxide alarm in any room used as living accommodation that contains a fixed combustion appliance, such as a gas boiler or wood burner (gas cookers are excluded)
• check the alarms work on the day a new tenancy starts
• repair or replace alarms once told they are faulty

A local council can serve a remedial notice, and a landlord who does not comply can face a civil penalty of up to £5,000.

A checklist for agencies

1. Record every property's gas safety expiry date, with the certificate attached.
2. Book the engineer in the two months before expiry to keep the original date.
3. Send the tenant their copy within 28 days, and to new tenants before move-in.
4. Keep every record until two further checks are done, and never for less than two years.
5. Log every access attempt and letter if a tenant will not let the engineer in.
6. Test smoke and CO alarms on the first day of every new tenancy and note the result.
7. Make sure contractors you send hold current Gas Safe registration.

For electrical safety, EPCs, deposits and Right to Rent, see the letting agent compliance checklist.

Keeping it on track in Letfold

In Letfold, gas safety certificates are stored against the property with their expiry date. Owners and managers get email reminders at 60, 30, 14 and 7 days before expiry, on the day, and after it lapses, so a renewal is booked before it becomes urgent. Contractors are held on file too, and a contractor whose insurance has lapsed cannot be assigned a job. See compliance tracking.

Frequently asked questions

How often does a landlord need a gas safety certificate?

Every 12 months, for each gas appliance and flue the landlord provides, carried out by a Gas Safe registered engineer.

When must tenants get a copy of the gas safety certificate?

Existing tenants within 28 days of the check, and new tenants before they move in.

Can a gas safety check be done early?

Yes. It can be done up to two months before the due date while keeping the original deadline, as long as records are kept until two further checks have been done.

How long must gas safety records be kept?

At least two years, and until two further checks have been carried out if you use the early renewal rule.

Does a landlord need a carbon monoxide alarm next to a gas boiler?

Yes, in England, where the boiler is in a room used as living accommodation. The rule covers fixed combustion appliances, but not gas cookers.

Sources

Checked on 17 September 2026:

• Gas safety - landlords and letting agents (HSE)
• Gas safety check records and what to keep (HSE)
• Dealing with tenants (HSE)
• Private renting: your landlord's safety responsibilities (gov.uk)
• Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022: guidance for landlords and tenants (gov.uk)

This article is general information for England, not legal advice.