What Temperature to Set Your Thermostat

A practical starting point is roughly 68 degrees Fahrenheit (20 degrees Celsius) in winter and about 78 degrees Fahrenheit (25 to 26 degrees Celsius) in summer while you are home and awake, with setbacks when you sleep or leave. These are general comfort-and-efficiency guidelines, not strict rules, and the ideal number depends on your household, home, and climate. This guide explains how to choose settings that balance comfort with lower energy bills.

The basic principle behind good settings

Heating and cooling systems use more energy the larger the gap between the indoor temperature you want and the temperature outside. In winter, the warmer you keep the house, the more the furnace or heat pump must run. In summer, the cooler you keep it, the more the air conditioner works. So the simplest rule is to keep the thermostat as close to the outdoor temperature as comfort allows, and to relax the setting further whenever you are asleep or away.

Suggested starting points by season

These numbers are widely cited comfort baselines. Treat them as a starting point and adjust to what your household actually finds comfortable.

There is nothing magic about any single figure. Some people sleep better in a cooler room and are happy to drop the winter setting more at night. Others run cold and prefer a slightly warmer baseline. Use the guidelines as a reference and fine-tune from there.

Why setbacks save money

A setback means letting the temperature move toward the outdoor temperature during hours when you do not need full comfort, such as overnight or during the workday. A common myth is that the system uses more energy recovering from a setback than it saved, so you might as well hold a constant temperature. In most homes the opposite is true: the energy saved during the setback outweighs the extra energy used to return to comfort.

• Overnight in winter, dropping the heat while everyone is under blankets is an easy saving.
• During a workday when the house is empty, letting it drift cuts hours of unnecessary running.
• In summer, raising the cooling setpoint while you are out reduces the air conditioner’s workload.

Comfort is more than a number

Two homes set to the same temperature can feel very different. Several factors shape how warm or cool a space feels beyond the thermostat reading:

Because of these effects, improving insulation, sealing drafts, and managing humidity can make you comfortable at a more efficient thermostat setting, sometimes more effectively than simply turning the dial.

Using fans and simple habits

A ceiling or portable fan cools people, not rooms, by helping sweat evaporate. That means you can often raise the summer setpoint a few degrees and stay comfortable if a fan is running, but there is no point leaving fans on in empty rooms. In winter, wearing warmer clothing indoors and using blankets lets you keep the heat a little lower without discomfort.

Programmable and smart thermostats

The biggest obstacle to saving energy is simply forgetting to adjust the temperature. Programmable thermostats solve this by following a schedule you set, automatically lowering the heat at bedtime and raising it before you wake, for example. Smart thermostats go further, learning your routine, sensing when the home is empty, and letting you adjust settings from your phone.

Whether the extra cost is worthwhile depends on how you currently behave. If you already manage a programmable thermostat carefully, the additional savings from a smart model may be modest. If you tend to leave the system running when you do not need it, automation can pay off.

Special situations to watch

• In very cold climates, do not lower the heat so far when away that pipes risk freezing.
• In hot, humid climates, avoid turning cooling off entirely for long periods, as moisture can build up.
• Homes with infants, elderly residents, or people with certain health conditions may need steadier, more moderate temperatures.
• Heat pumps can behave differently from furnaces during recovery, so large sudden setbacks may be less efficient with some systems.

Adjusting as the seasons change

Spring and autumn are the easiest times to save, because outdoor temperatures often sit close to what you find comfortable indoors. On mild days you may not need heating or cooling at all: opening windows in the cool of the morning or evening, then closing them to trap comfortable air, can carry a home through much of a shoulder season. Treat the thermostat as a backstop for the extremes rather than a switch you leave running year round.

It also pays to revisit your settings when your routine changes. A new work-from-home schedule, a different sleep pattern, or a change in who lives in the home can all shift when comfort is actually needed. A setting that made sense a year ago may now be heating or cooling an empty house, so a quick review every few months keeps your schedule matched to real life.

The best thermostat setting is ultimately the one that keeps your household comfortable while running the system no more than necessary. Start from the seasonal baselines, use setbacks when asleep or away, address comfort factors like drafts and humidity, and let a programmable or smart thermostat handle the routine for you.

Frequently asked questions

What temperature should I set my thermostat in winter?

A common comfort baseline is around 68 degrees Fahrenheit, or about 20 degrees Celsius, while you are home and awake. Many people are comfortable a little lower with a sweater, and lowering the setting several degrees at night or when out reduces heating costs. The best number is the lowest one that still feels comfortable to your household.

What temperature should I set my thermostat in summer?

A frequently recommended setting is about 78 degrees Fahrenheit, roughly 25 to 26 degrees Celsius, when you are home and the air conditioning is running. Raising the temperature when you are away or asleep saves energy because the system runs less. Fans can make a room feel a few degrees cooler, letting you keep the thermostat higher.

Does lowering the thermostat at night save money?

Yes, in most homes reducing the heat while you sleep lowers energy use because the heating system runs less over those hours. The same idea applies to raising the cooling setpoint in summer. A programmable or smart thermostat makes this automatic so you do not have to remember to adjust it.

Is it cheaper to leave the thermostat at one temperature all day?

Generally no. The idea that a system works harder to recover from a setback usually costs less than the energy saved during the setback period. For most homes, letting the temperature drift toward the outdoor temperature while you are away and then returning it to comfort saves more than holding a constant setting.

What thermostat setting is best when I am away from home?

When the house is empty, you can let the temperature drift further from your comfort zone, such as cooler in winter and warmer in summer, to cut energy use. Avoid extremes that could freeze pipes in very cold weather or let humidity build up in hot, damp climates. A setback of several degrees is a practical starting point.

Why does my house feel cold even at a normal thermostat setting?

Perceived comfort depends on more than the thermostat number. Drafts, poor insulation, low humidity, and cold surfaces like windows can make a room feel colder than the air temperature suggests. Sealing drafts, adding insulation, and managing humidity often improve comfort more than simply turning up the heat.

Are smart thermostats worth it?

For many households they help by automating setbacks, learning your schedule, and letting you adjust the temperature remotely. The value depends on how much you would otherwise leave the system running when it is not needed. If you already adjust a programmable thermostat carefully, the extra savings may be smaller.