What Temperature Should You Keep Your House in Winter?

The U.S. Department of Energy's advice for winter is to set the thermostat at 68°F or lower while you're awake and home, at the lowest temperature you're comfortable with, and to set it back further while you're asleep or away. Never set the heat below 55°F when you're away; that's the American Red Cross minimum for keeping pipes from freezing. Some people need it warmer. The World Health Organization calls 18°C (about 64°F) a safe indoor temperature for most people in cold weather, and says older people, children, and people with chronic illnesses, especially heart and lung disease, may need a higher minimum. The National Institute on Aging tells older adults to set the heat to at least 68°F.

Winter Thermostat Settings at a Glance

If the house feels cold at 68°F, the fix may be drafts or insulation rather than a higher setting. One room colder than the rest covers the usual culprits.

How Much Turning the Heat Down Saves

The Department of Energy's Energy Saver guide puts it this way: "You can save as much as 10% per year on heating and cooling by turning your thermostat down 7°–10°F for 8 hours a day in the fall and winter." The DOE's consumer guide to heating and cooling gives a rule of thumb for the overnight setback: you can save 1% on heating bills for each 1°F you set it back during an eight-hour period. It adds a fair warning: keep your comfort in mind, because a setting that's too low isn't worth it.

Let a schedule do it. The DOE says a programmable thermostat runs the heat on a schedule you set, and a smart thermostat can learn the temperatures you like and drop to energy-saving settings when you're asleep or away. Our smart thermostat guide covers the picks and how their schedules and away modes work. If your thermostat isn't holding its schedule, or the house never reaches the setting, start with thermostat not working.

When not to set it back. During a hard freeze, the Red Cross says to keep the thermostat at the same temperature day and night. You may pay a bit more for heat for a few nights, it says, but you can prevent a much more costly repair if a pipe freezes and bursts. Check the pipe freeze forecast for your zip code on cold nights.

If You Have a Heat Pump

Heat pumps are the exception to "turn it way down." Most have backup electric-resistance heat, often called auxiliary (AUX) or strip heat, that kicks in when the heat pump alone can't keep up. A big jump in the setting, like coming back up 10°F in the morning, can be just what turns it on. The DOE's advice is direct: don't set back a heat pump's thermostat manually if it causes the backup electric-resistance heat to come on, because that heat is more expensive. Google puts a number on it: AUX heat can cost about 2 to 5 times as much as running the heat pump.

What to do instead:

• Use a thermostat built for heat pumps. The DOE says to set back a heat pump only with a smart or programmable thermostat designed for use with heat pumps.
• Look for the backup-heat settings. Google's Nest thermostats, for example, have a Heat Pump Balance setting for how much AUX heat the system uses.
• Keep manual setbacks small. If you change the setting by hand, a few degrees is a safer bet than a big drop. If you notice "Aux" or "Emergency heat" lighting up after every setback, the setback is costing you, not saving.

If a heat pump is blowing cool air or iced over, see heat pump blowing cold air or heat pump frozen.

Protecting Pipes When You're Away

The Red Cross is clear: if you'll be away during cold weather, leave the heat on, set no lower than 55°F. Texas A&M AgriLife Extension and the Insurance Institute for Business & Home Safety give the same 55°F minimum.

Before you leave in winter:

1. Set the heat to 55°F or higher and confirm the thermostat is in heat mode with fresh batteries if it uses them.
2. Open the kitchen and bathroom cabinet doors, especially on outside walls, so warm air can reach the plumbing (Red Cross, IBHS). Move cleaners and chemicals out of reach of children and pets first.
3. Keep the garage door closed if water lines run through the garage (Red Cross).
4. Shut off and drain the outdoor faucets and disconnect the hoses; our outdoor faucet guide walks through it.
5. For a long trip, shut off the main water valve too, and keep the heat on. Prince William Water, a Virginia water utility, lists shutting off the main as a way to protect pipes during extended absences in winter, and the District of Columbia's insurance regulator says a vacant house without heat should have the water supply shut off and the system and appliances drained. Ask a plumber if you're unsure how to drain your system.
6. Ask someone to check the house, and call your insurer about how your policy treats an empty house in winter. DC's insurance regulator suggests having a neighbor check on a vacant property.

If you come home to a faucet that gives only a trickle, a pipe is probably frozen: see frozen pipes: what to do.

Who Needs the House Warmer

Older adults. The National Institute on Aging says to set the heat to at least 68°F, and warns that even mildly cool homes, from 60 to 65°F, can lead to hypothermia in older adults. Aging can make it harder to notice the body getting too cold, NIA adds. CDC says to check on older friends and neighbors often to make sure their homes are heated properly.

Babies. CDC says infants under one year old should never sleep in a cold room, because they lose body heat more easily than adults. It suggests warmer sleep clothing and no pillows or soft bedding in the sleep area.

People with health conditions. WHO's housing and health guidelines call 18°C (about 64°F) a safe and well-balanced indoor temperature for general populations in the cold season, and say a higher minimum may be needed for older people, children, and people with chronic illnesses, particularly heart and lung disease. If someone in the house has a medical condition, ask their doctor what's right.

Using a Space Heater

A space heater can warm the room you're in without heating the whole house, but follow the rules every time. Keep it at least 3 feet from anything that can burn, plug it straight into a wall outlet, never an extension cord or power strip, and turn it off and unplug it when you leave the room or go to sleep (CPSC, NFPA). Our space heater safety rules cover the rest.

Frequently Asked Questions

What temperature should I set my thermostat when I'm away in winter?

For a workday, set it back 7–10°F from your usual setting; the DOE says that for 8 hours a day can save as much as 10% a year on heating and cooling. For a trip, the Red Cross says to leave the heat on and set no lower than 55°F. Never go below 55°F, and open the sink cabinets on outside walls before you go.

Is 62 too cold for a house?

It depends on who's home. For a healthy household, 62°F is a common overnight or away setback, and it's well above the 55°F floor for pipes. But it's below the 18°C (about 64°F) that WHO calls a safe indoor temperature in the cold season, and NIA warns that homes from 60 to 65°F can lead to hypothermia in older adults. With an older adult, a baby, or someone with a heart or lung condition at home, keep it warmer.

What temperature do pipes freeze in a house?

Water freezes at 32°F, but pipes inside a heated house rarely get that cold. The ones at risk run through unheated or poorly insulated spaces: attics, crawl spaces, garages, basements, exterior walls, and sink cabinets on outside walls (Red Cross, Texas A&M AgriLife Extension). Texas A&M says pipes can freeze and burst when the outside temperature reaches 20°F or below. Keeping the heat at 55°F or higher protects the pipes inside the house; our pipe freeze forecast shows when your area is at risk.

Does turning the heat down at night save money?

Yes. The DOE says you can save about 1% on heating bills for each degree you set back for an eight-hour stretch, and as much as 10% a year by setting back 7–10°F for 8 hours a day. The exceptions: with a heat pump, keep setbacks small or use a heat-pump thermostat so the backup heat doesn't come on, and in extreme cold, the Red Cross says to keep the setting steady day and night to protect the pipes.

The Bottom Line

Set the thermostat to 68°F or lower while you're up and home, and set it back 7–10°F while you sleep or are out; the DOE says that can save as much as 10% a year. Never set the heat below 55°F when you're away. Keep it at 68°F or more for older adults, keep a baby's room warm, and keep heat-pump setbacks small. Let a programmable or smart thermostat handle the schedule so the savings happen every day.

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