What Temperature Should You Set Your Thermostat?
The Department of Energy suggests around 68°F in winter while you're awake, and setting it lower while asleep or out. In summer, set it as high as is comfortable. The setback — the gap between occupied and unoccupied temperatures — saves more than any single number.
Most thermostat advice fixates on a single number. The number matters less than the pattern: how far you let the house drift when nobody needs it comfortable, and for how many hours a day.
The starting points
- Winter: around 68°F while you're awake and at home, lower while asleep or away.
- Summer: as high as you find comfortable, and higher still when the house is empty.
- Consistency beats micromanagement — repeatedly overriding a schedule usually erases the benefit.
The physics is simple. Heat moves from warm to cold, and faster the bigger the difference. Letting your house sit closer to outdoor temperature while you're out means less heat escaping, so less energy to replace.
The heat pump exception
What it's worth in dollars
Heating and cooling is the largest single load in most U.S. homes, so a percentage change here moves more money than anything you can unplug. The exact figure depends on your climate zone, your fuel, your insulation, and your local rate — which is why we won't quote a single national number.
To put a figure on your own home, run your bill and local rate through the calculator below rather than trusting a generic percentage.
When this advice changes
- Very humid climates: cooling is partly a dehumidification job, so raising the setpoint too far can make a house feel worse at the same temperature.
- Homes with radiant floors or high thermal mass respond slowly; frequent setbacks work poorly.
- If anyone at home is medically vulnerable, comfort and safety outrank the saving.
| Household | Realistic setback window | What to expect |
|---|---|---|
| Empty 9-5, sleeps 8h | 16 hours a day | Largest opportunity — two setback periods |
| Someone home all day | Overnight only | Smaller, but the overnight setback still counts |
| Shift work, irregular | Varies daily | Manual scheduling fails; occupancy-based control does better |
| Heat pump, cold climate | Shallow, thermostat-managed | Deep manual setbacks can call in backup heat and cost more |
What to do next
Pick one setback you'll actually keep — most people start with the eight hours they're asleep — and leave it in place for a full billing cycle before judging it. If you don't want to think about it again, that's the honest case for a programmable or smart thermostat.
Sources
- Thermostats — U.S. Department of Energy — Energy Saver. Consulted July 22, 2026.
- Energy Saver: Save Energy, Save Money — U.S. Department of Energy. Consulted July 22, 2026.
- Residential Energy Consumption Survey (RECS) — U.S. Energy Information Administration. Consulted July 22, 2026.
Frequently asked questions
Is 68°F really the right winter setting?
It's the Department of Energy's suggested starting point for waking hours, not a rule. What matters more is lowering it while you sleep or are out — that gap is where the saving comes from.
Does turning the thermostat way down save more?
For a furnace, a deeper setback generally saves more. For a heat pump, a large manual setback can call in electric backup heat on recovery and cost you more, so let the thermostat manage it.
Is it cheaper to leave the heating on all day?
No. A house loses heat faster the warmer it is relative to outside, so letting it cool while you're out reduces total loss. The 'leave it on constantly' idea doesn't hold for most homes.