What Temperature Should You Set Your Thermostat in Winter?

Ask the internet and you’ll get one answer: “Set it to 68°F (20°C).” It’s a fine starting point — but it’s not the whole story. The truth is there is no single magic number, because comfort doesn’t come from the air temperature alone.

Why a fixed number doesn’t work

Your body loses heat in several ways at once: to the air around you, but also by radiation to the cold surfaces of the room. On a bitter −1°C day, your walls and windows are noticeably colder than on a mild +5°C day. Those cold surfaces pull heat from your body, so the room feels colder — even though your thermostat reads the same 20°C both days.

Add humidity (dry winter air feels cooler) and draughts from wind, and you can see why the same setting gives different comfort on different days.

A practical baseline

As a rule of thumb for living spaces in winter:

Living rooms: 19–21°C (66–70°F) when you’re home and active.
Bedrooms: 16–18°C (61–64°F) — cooler is better for sleep.
Empty house / overnight: 15–16°C (59–61°F) to save energy.

Each degree lower can cut heating energy use by roughly 6–7%, so the goal is the lowest setting that still feels comfortable — not the highest.

Adjust for the weather, not just the calendar

The smart move is to nudge your setting based on conditions:

Very cold or windy outside? Raise the setting half a degree to a degree to offset cold walls and draughts.
Mild and still? You can usually drop it and feel just as comfortable.
Very dry air indoors? Adding humidity (a bowl of water, a humidifier) makes the same temperature feel warmer.

This is exactly the gap SetMyTemp fills: it reads your local weather in real time and tells you the setting that genuinely feels right today, so you stop guessing.

Frequently asked questions

Is 20°C too low for winter? Not at all — 19–21°C is the recommended comfort range for active living spaces. If you feel cold at 20°C, the cause is often cold walls or draughts, not the air temperature itself.

Should I leave the heating on all day? For most homes it’s cheaper to heat when you need it and let the temperature drop when you’re out or asleep, rather than holding one temperature around the clock.

See the live recommendation for your city — for example London or New York — or open the SetMyTemp tool.