Best Thermostat Settings for Winter: Day, Night, and Away

Quick answer

The U.S. Department of Energy (DOE) suggests setting your thermostat around 68°F to 70°F while you’re home and awake, and lower while you sleep or are away. Turning it back 7°F to 10°F for 8 hours a day can save, in the DOE’s words, “as much as 10% a year on heating and cooling.” Three cases call for a different plan: with a heat pump, ENERGY STAR advises one steady temperature; a home with an older adult should stay at 68°F or warmer, according to the National Institute on Aging; and if you leave in cold weather, the American Red Cross says to keep the heat no lower than 55°F to protect your pipes.

A winter thermostat schedule

Treat this as a starting point. The DOE’s advice is to set the thermostat as low as is comfortable when you’re home, so adjust from here.

Situation	Setting	Basis
Home and awake	Start around 68°F to 70°F, then go as low as is comfortable	DOE Energy Saver
Asleep	7°F to 10°F below your daytime setting (about 58°F to 63°F)	DOE: a 7°F to 10°F setback for 8 hours a day
House empty for 4 hours or more	The same setback as for sleep	DOE: adjust for periods when no one is home 4 hours or more
Away for days in cold weather	Heat on, no lower than 55°F	American Red Cross
Very cold night, pipes at risk	The same temperature day and night	American Red Cross
An older adult lives in the home	At least 68°F	National Institute on Aging
Heat pump	One steady, comfortable temperature, unless your thermostat is designed for heat pump setbacks	ENERGY STAR and DOE

The sleep and away range assumes a daytime setting of 68°F to 70°F. When a safety row applies to your home, it overrides the savings rows. Source: DOE Energy Saver, ENERGY STAR, National Institute on Aging, American Red Cross (listed under Sources)

How much a setback saves

Here is the DOE’s figure exactly as its Energy Saver program states it: “You can save as much as 10% a year on heating and cooling by simply turning your thermostat back 7°-10°F for 8 hours a day from its normal setting.”

Four details in that sentence are easy to miss:

• “As much as” is a ceiling. It is not a promised saving.
• It covers heating and cooling together. The DOE’s 2022 Energy Saver guide pairs the winter setback with turning the thermostat up in spring and summer.
• Climate matters. The DOE says the percentage saved is greater in milder climates than in severe ones.
• It does not apply the same way to every heat pump. See the heat pump section below.

What 10% can look like in dollars. ENERGY STAR says the average American household spends more than $900 a year on heating and cooling. Ten percent of $900 is $90, so for a household near that average, “as much as 10%” means savings of up to about $90 a year. If your heating and cooling costs are higher or lower, scale it the same way: yearly heating and cooling cost × 0.10 gives the top of the range.

Doesn’t the furnace work harder to warm the house back up?

The DOE calls this a common misconception. As soon as your house drops below its normal temperature, it loses heat to the outdoors more slowly. The longer it stays at the lower temperature, the more energy you save, because the house has lost less heat than it would have at the higher setting. The main exception is a heat pump that turns on expensive backup heat to recover, covered below.

What to set the thermostat to at night

With a daytime setting of 68°F to 70°F, the DOE’s 7°F to 10°F setback works out to about 58°F to 63°F overnight. A few DOE tips make that easier to live with:

• Start the setback before bed. If you like to sleep cool, the DOE suggests starting the setback a little ahead of the time you actually go to bed.
• Let the thermostat warm the house before you wake. A programmable or smart thermostat can return the temperature to normal before you get up, so you don’t wake to a cold house.
• Plan around everyone’s schedule. The DOE says to consider the schedules of everyone in the household when you program it.

If 58°F is too cold for your household, a smaller setback is still an option. Just know that the DOE’s 10% figure is for 7°F to 10°F; the DOE does not give a savings number for smaller setbacks.

Skip or limit the nighttime setback if someone in the home is an older adult (see the safety section), if you have a heat pump without a heat-pump-ready thermostat, or on very cold nights when your pipes could freeze. The Red Cross advises keeping the same temperature day and night in that situation. It notes that pausing the lower nighttime setting may raise your heating bill, but it can prevent a much more costly repair if pipes freeze and burst.

When you’re away

During the workday. The DOE says that if your house is empty for 4 hours or more during the day, it makes sense to set the temperature back for those hours. Some ENERGY STAR certified smart thermostats use geofencing to detect when you leave, set the system back, and bring the house back to your preferred temperature when you’re on the way home.

Away for days. The American Red Cross says to leave the heat on and set it no lower than 55°F if you’ll be away during cold weather. The Red Cross lists the pipes that freeze most often:

• Pipes exposed to severe cold, such as outdoor hose bibs, swimming pool supply lines, and sprinkler lines
• Water pipes in unheated areas such as basements, crawl spaces, attics, garages, and kitchen cabinets
• Pipes that run along exterior walls with little or no insulation

Other Red Cross steps for cold snaps:

• Keep garage doors closed if water lines run through the garage.
• Open kitchen and bathroom cabinet doors so warmer air reaches the pipes. Move cleaners and chemicals out of children’s reach first.
• When it is very cold outside, let cold water drip from a faucet served by exposed pipes.

Heat pumps: go easy on setbacks

The usual setback advice is written for furnaces and boilers. ENERGY STAR puts it plainly: unlike a furnace or boiler, heat pumps do not save energy by turning the temperature down when you’re away or asleep. Its advice is to pick a comfortable temperature and leave it there.

Why. Some heat pump systems come with a second heat source called auxiliary (AUX) heat, according to Google’s Nest help pages. The DOE describes this backup as electric resistance heat and notes it is more expensive to run. Nest says AUX heat can come on when it is too cold outside, when the heat pump needs to defrost, or to change the indoor temperature quickly. Warming the house back up after a deep setback is exactly that kind of quick change. Nest estimates that AUX heat can cost about 2 to 5 times as much as running the heat pump itself.

The DOE says the same thing from the other direction:

• Its thermostat guidance says setting back a heat pump in heating mode can make the unit run inefficiently, canceling out the savings, and that a moderate setting is the most cost-effective practice.
• Its 2022 Energy Saver guide says not to set back a heat pump’s thermostat manually if it causes the backup electric resistance heat to come on.

When setbacks can work. The DOE notes that some companies sell programmable thermostats designed for heat pumps. They use special algorithms to keep backup heat to a minimum, which makes a setback cost-effective. The DOE’s guide says not to do the 7°F to 10°F setback on a heat pump without a smart or programmable thermostat designed for heat pumps.

What to check on your thermostat:

1. Make sure the heat pump is set to Heat, not Auto. ENERGY STAR advises this so the system doesn’t switch modes on unusually warm or cold days.
2. Look for an AUX heat setting. Check whether your thermostat lets you control how readily AUX heat comes on. Google Nest thermostats, for example, have a Heat Pump Balance setting that offers Max Comfort (the default, which uses AUX heat sooner and more often), Balanced, and Max Savings (which uses it later and less often). Nest notes that how much AUX heat you use still depends on your system.
3. If you’re not sure, keep it steady. Without a heat-pump-ready thermostat, ENERGY STAR’s one-temperature advice is the safe choice for your bill.

For what AUX and EM HEAT mean and what each costs to run, see aux heat vs. emergency heat. If the heat pump runs and runs but the house never reaches the set temperature, that is a different problem. See why a heat pump is not heating.

Minimum safe settings

Other things that affect comfort and cost

• Where the thermostat is. The DOE says a thermostat should be on an interior wall, away from direct sunlight, drafts, doorways, skylights, and windows, with no furniture in front of or below it. A badly placed thermostat can get false readings and run the system when it doesn’t need to.
• Ceiling fans. The DOE’s guide says to reverse ceiling fans in winter so they run clockwise and push warm air down from the ceiling.
• Radiant floors and steam heat. These respond slowly, up to several hours, according to the DOE. Start the setback well before you leave or go to bed, and schedule the return to normal 2 to 3 hours before you wake up or get home. The DOE notes that some thermostats track how your heating system performs and decide when to turn it on so the house is comfortable at the programmed time.
• Electric baseboard heat. It needs a line-voltage thermostat that directly controls 120-volt or 240-volt circuits, and the DOE notes that only a few companies make programmable ones. Installing one means working on line-voltage wiring, so leave it to a licensed electrician.
• Smart or programmable? The DOE’s guide says programmable thermostats are cheaper, while smart thermostats are usually easier to use and offer more reporting. ENERGY STAR certified smart thermostats have been independently certified, based on actual field data, to deliver energy savings.