By Mario Vaghei, General Manager, Aire One Peel Heating & Cooling · Published November 2, 2026 · Facts verified October 30, 2026
Short answer
There is no single right number. The setting that saves money is a lower one at night and while the house is empty. In a Canadian government test house heated by a gas furnace, lowering the thermostat from 22°C to 18°C overnight used 6.5% less natural gas. Setting it to 16°C at night and while the house was empty during the day used 13% less. Pick a daytime temperature your household is comfortable with, then set it back.
On this page
What the Canadian test found · A simple winter schedule · If you have a heat pump · Comfort is not only the number · More ways to cut the heating bill · Talk to us · Frequently asked questions
What the Canadian test found
Statistics Canada reported a 2003 test by the Canadian Centre for Housing Technology. Two identical test houses were compared, one used as the benchmark at a steady 22°C.
| Setting | Gas saved compared with a steady 22°C |
|---|---|
| 22°C all day and night (benchmark) | 0% |
| 18°C at night | 6.5% |
| 16°C at night and while the house is empty in the day | 13% |
Table: Statistics Canada, "Thermostat use in Canadian homes" (EnviroStats, catalogue 16-002-X), reporting the 2003 Canadian Centre for Housing Technology test. Read October 30, 2026.
Two cautions. The test used one mid-efficiency gas furnace in test houses with no people living in them. Your savings depend on your home's insulation, your furnace and your habits.
A simple winter schedule
- Home and awake: the temperature your household finds comfortable.
- Asleep: a few degrees lower. The test's 18°C overnight setting saved 6.5%.
- Everyone out for the day: lower again. The test's 16°C at night and when away saved 13%.
- Away on a trip: keep the heat on at a lower setting rather than off, so pipes and the house stay protected.
A programmable or smart thermostat does this for you, so you do not have to remember. Our guide to smart thermostats explains the options.
If you have a heat pump
The test above used a gas furnace. Heat pumps and dual-fuel systems can respond differently to a large setback, depending on how the system and its backup heat are set up. Ask your installer what setback and recovery settings suit your system before you program deep setbacks.
Comfort is not only the number
- Humidity. Dry winter air can make a room feel colder than the thermostat says. Our indoor humidity guide sets out the levels Ontario homes should aim for.
- Thermostat location. A thermostat near a supply register, a lamp or a sunny window reads warm and leaves other rooms cold.
- Filter and maintenance. A clogged filter and a furnace that has not been serviced take longer to reach the set temperature.
More ways to cut the heating bill
Our guide to lowering your heating bill in Ontario has the next steps after the thermostat.
Talk to us
If some rooms never reach the set temperature, the cause may be airflow, the thermostat or the furnace. Book a visit and we will find it. We serve Mississauga, Brampton, Etobicoke, Milton, Georgetown, Caledon and Bolton. Call 905-564-8545.
Frequently asked questions
What is the best thermostat setting for winter in Ontario?
Use a temperature your household is comfortable with when you are home and awake, and set it lower at night and when the house is empty. In a Canadian test house, 18°C at night instead of a steady 22°C saved 6.5% of gas.
How much can I save by turning the thermostat down at night?
In the 2003 Canadian Centre for Housing Technology test, a night setback from 22°C to 18°C used 6.5% less natural gas. Setting it to 16°C at night and while the house was empty saved 13%. Results vary by home.
Is it cheaper to leave the heat at one temperature all day?
Not in the Canadian test. The settings with a night setback, and a setback while the house was empty, used less gas than holding a steady 22°C.
Should I turn the heat off when I go on vacation in winter?
No. Keep it on at a lower setting so pipes and the house stay protected.
Do thermostat setbacks work with a heat pump?
They can, but heat pumps and dual-fuel systems may respond differently to a large setback. Ask your installer about setback and recovery settings for your system.
Sources and references
- Statistics Canada, "Thermostat use in Canadian homes", read October 30, 2026.