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England · Compliance & safety

Smoke and carbon monoxide alarm requirements — what UK landlords must comply with in 2026

The Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022 require CO alarms in every room with a combustion appliance. Here is every rule that applies to your rental property in 2026, the penalties for non-compliance, and what to check before your next new tenancy.

7 min readUpdated 12 June 2026Last reviewed: 17 May 2026Smoke AlarmsCarbon MonoxideComplianceSafety
Quick answer

From 1 October 2022: smoke alarm on every storey used as living accommodation; CO alarm in every room with a fixed combustion appliance (gas boiler, gas fire, oil appliance, solid-fuel burner). Test all alarms at the start of every tenancy. Penalty for non-compliance: civil penalty up to £5,000. The rules apply to all residential tenancies in England.

The Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022 significantly extended the CO alarm duty that existed since 2015. If you have not reviewed your alarm setup since October 2022, this guide explains what is now required and what local councils can do if you fail to comply.

The smoke alarm duty

Regulation 4 of the Smoke and Carbon Monoxide Alarm (England) Regulations 2015 (as amended) requires a landlord to ensure a smoke alarm is installed on each storey of the property that is used as living accommodation. The alarm must be in proper working order at the start of the tenancy.

  • One smoke alarm per storey, on every floor used as living accommodation
  • Must be in proper working order at the commencement of the tenancy
  • The landlord must test the alarm (not the tenant) on the first day of the tenancy
  • Hallways, landings, and corridors count as living accommodation for this purpose
  • Alarm type: at minimum, an audible battery or mains-powered alarm meeting BS EN 14604. Interconnected alarms are best practice but not mandated

The carbon monoxide alarm duty — updated October 2022

Before 1 October 2022, CO alarms were only required in rooms with solid-fuel burning appliances. The 2022 amendment extended the duty to all rooms containing a fixed combustion appliance used as living accommodation.

  • CO alarm required in every room used as living accommodation that contains a fixed combustion appliance
  • Fixed combustion appliances include: gas boilers (even in utility cupboards that form part of the living accommodation), gas fires, oil-fired boilers, solid-fuel stoves, wood burners, and biomass appliances
  • Gas cookers in kitchens used only for cooking are excluded from the duty — though installation is strongly recommended
  • The alarm must meet BS EN 50291:2018 and be in working order at the commencement of the tenancy
  • Landlord must test the CO alarm on the first day of the tenancy
Gas boiler in a cupboard?

If the boiler cupboard forms part of the living accommodation — even if it is a small airing cupboard off the hallway — you need a CO alarm in that space or in the room immediately adjoining it where the alarm can be triggered by CO escaping from the appliance. If in doubt, fit alarms in both the cupboard and the adjacent room.

Testing obligations

The regulations place the testing duty on the landlord, not the tenant. You must test all smoke and CO alarms on the first day of each new tenancy. For ongoing tenancies the duty passes to the tenant to report any faults, but good practice (and many tenancy agreement clauses) requires periodic landlord checks during inspections.

  • Test every smoke alarm and CO alarm on the first day of the tenancy — press the test button until the alarm sounds
  • Record the test date, findings, and any replacements in your property file
  • Replace battery alarms when the low-battery warning sounds — do not wait until inspection
  • Replace CO alarms at the manufacturer's stated service life (typically 7–10 years from manufacture date, not installation date)
  • If a tenant reports a faulty alarm, replace it promptly — failure to do so is both a regulatory breach and a potential HHSRS Category 1 hazard

HMOs — additional requirements

HMOs must comply with the 2015/2022 alarm regulations AND the HMO Management Regulations 2006 (or 1990 for older HMOs). The Management Regulations impose fire safety obligations that go beyond the alarm duty:

  • Fire detection and warning system appropriate to the size and layout of the HMO — typically a Grade D, Category LD2 or LD1 system in larger HMOs
  • Fire-fighting equipment: fire blanket in the kitchen, fire extinguishers in common areas where required by a fire risk assessment
  • Emergency lighting in common parts where appropriate
  • Fire doors to individual letting rooms and kitchens in HMOs of three or more storeys
  • The HMO licence conditions will specify the minimum fire-safety standard for your property — comply with those as a floor, not a ceiling

Enforcement and penalties

Local housing authorities enforce the smoke and CO alarm regulations. The enforcement process works as follows:

  1. The council identifies a breach — typically via a tenant complaint, a licensing inspection, or an Environmental Health visit
  2. The council serves a remedial action notice specifying the action required and allowing 28 days to comply
  3. If the landlord fails to comply within 28 days, the council may arrange for the alarms to be installed and recover the cost from the landlord
  4. The council may also impose a civil penalty of up to £5,000 for the breach
  5. Repeat failures or egregious cases may also trigger HHSRS enforcement and improvement notices, or affect the landlord's fitness to hold an HMO licence
Insurance implications

Some landlord buildings insurance policies require smoke detection equipment to be in working order as a condition of cover. A fire at a property where you cannot demonstrate the alarms were tested and working may result in a claim being reduced or refused. Check your policy wording.

What to check before your next new tenancy starts

  1. Walk every storey used as living accommodation — is there a working smoke alarm on each? Replace any alarm over 10 years old
  2. Identify every room used as living accommodation that contains a fixed combustion appliance — is there a working CO alarm in each? Replace any alarm beyond its service life
  3. Press the test button on every alarm. If it does not sound, replace immediately — do not let a new tenancy start without working alarms
  4. Record the test in your pre-tenancy checklist — date, rooms tested, alarm type, and result
  5. Repeat the test on the first day of the tenancy in the tenant's presence and note it in the tenancy check-in document

Frequently asked questions

Do I need a carbon monoxide alarm in every room in my rental property?+

No — you need a CO alarm in every room used as living accommodation that contains a fixed combustion appliance (for example a gas boiler, gas fire, oil boiler, or solid-fuel appliance). Rooms with only a gas cooker do not require a CO alarm under the 2022 regulations, although installation is best practice. Every room with a gas boiler, gas fireplace, oil-fired appliance, or solid-fuel burner does require a CO alarm.

When did the carbon monoxide alarm rule change?+

The Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022 came into force on 1 October 2022. Before that date, CO alarms were only required in rooms with solid-fuel burning appliances. From 1 October 2022 the duty was extended to rooms with any fixed combustion appliance — covering gas boilers, gas fires, and oil appliances.

What type of CO alarm is required?+

The regulations require a carbon monoxide alarm that is in proper working order. In practice this means an audible CO alarm meeting BS EN 50291:2018. Battery-operated alarms are acceptable; hard-wired alarms are not specifically required. Interconnected alarms are not mandated by regulation but are recommended best practice for larger properties and HMOs.

What is the penalty for not having smoke or CO alarms?+

A local housing authority can serve a remedial action notice on a landlord who fails to have the required alarms fitted. If you fail to comply within 28 days, the council can arrange for the alarms to be fitted and recover the cost, plus impose a civil penalty of up to £5,000. The local authority must take into account any relevant circumstances before issuing a penalty.

Do smoke and CO alarm rules apply to HMOs?+

Yes, the Smoke and Carbon Monoxide Alarm Regulations 2015 and 2022 amendments apply to all residential premises in England let under a tenancy, including HMOs. HMOs are also subject to the HMO Management Regulations 2006, which impose additional requirements for fire detection and fire-fighting equipment. The two sets of rules operate in parallel — you must comply with both.

Templates recommended in this guide

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