Carbon monoxide and smoke alarm law in Ontario: what landlords must do in 2026

Smoke alarms: every storey and outside sleeping areas

By law, every Ontario home must have working smoke alarms on every storey and outside all sleeping areas. That applies to rented homes as much as owner-occupied ones, and to each unit in a house with a basement apartment.

In a rental, the landlord is responsible for installing smoke alarms and keeping them working. If they run on batteries, the landlord supplies the batteries and makes sure they're changed. Test them monthly where you can, and always before a new tenant moves in; the start of a tenancy, when you're preparing the unit and the lease, is the natural moment. If you're looking for that tenant, see our tenant placement service.

Carbon monoxide alarms: what changed on January 1, 2026

Carbon monoxide alarms were already required beside each sleeping area in homes with a source of carbon monoxide. Updates to the Ontario Fire Code that took effect on January 1, 2026 added two things:

• Every storey. Homes with a fuel-burning appliance, a fireplace or an attached garage now also need a carbon monoxide alarm on each storey, including floors without bedrooms, such as a main floor or a basement.
• More buildings. The rules now cover homes heated by air from a fuel-burning appliance located outside the home, such as a furnace in a building's service room, and apartment and condo buildings need alarms in public corridors where fuel-burning equipment serves the building.

Alarms go on ceilings or high on walls, as the manufacturer's instructions say. One alarm in a hallway can cover several bedrooms off it.

Which homes need carbon monoxide alarms

A home needs them if it has any source of carbon monoxide:

• a fuel-burning appliance, such as a gas or oil furnace, boiler, water heater, stove or dryer;
• a wood or gas fireplace;
• an attached garage;
• in a condo or apartment, a service room or garage directly above, below or beside the unit, or heating supplied by a fuel-burning appliance outside the unit.

A fully electric home with no fireplace and no attached garage doesn't need them, though many owners install them anyway.

Who does what in a rental

To check alarms when a tenant is living there, a landlord gives 24 hours' written notice and enters between 8 a.m. and 8 p.m., as for any inspection. A tenant who disables an alarm can be charged, and a tenant whose landlord doesn't provide working alarms can call the local fire department; in Toronto, 311 refers it to Toronto Fire Services.

Making alarm testing and reporting a written part of the tenancy helps everyone. Our guide to landlord rights and responsibilities covers entry and repairs in more detail.

Choosing alarms

Alarms must meet Canadian standards. They can be hard-wired, battery-operated or plug-in, as the Fire Code allows for the location, and combination smoke and carbon monoxide alarms can meet both requirements. Every alarm has an end-of-life date printed on it; replace it by then, even if it still sounds when tested.

In a basement apartment or other second unit, each unit needs its own alarms. Interconnected smoke alarms, where one sets off the others, are part of the fire safety rules for many second units, so check the requirements that applied when the unit was built or registered.

The fines

Fire Code offences are prosecuted under the Fire Protection and Prevention Act. The City of Toronto lists fines of up to $50,000 and up to a year in jail for an individual, and up to $500,000 for a corporation. Fire departments can also issue tickets on the spot for missing or disabled alarms.

A checklist before each new tenancy

• A smoke alarm on every storey and outside each sleeping area, in every unit.
• If there's any fuel-burning appliance, fireplace or attached garage: a carbon monoxide alarm beside each sleeping area and on every storey.
• Every alarm tested, with fresh batteries where it uses them.
• No alarm past its end-of-life date.
• The manufacturer's instructions given to the tenant, and the test noted on the move-in inspection.
• The tenant told how to report a problem, and asked to test monthly.

Sources

• City of Toronto, Carbon monoxide alarms (updated January 5, 2026)
• Town of Newmarket, New carbon monoxide alarm requirements coming into effect on January 1, 2026 (December 29, 2025)
• Ontario Association of Fire Chiefs, Ontario updating Fire Code to expand mandatory carbon-monoxide alarms (December 7, 2025)
• City of Barrie, Landlord fire safety responsibilities
• Landlord and Tenant Board, A Guide to the Residential Tenancies Act