Thermostat settings by state
Thermostat settings in Washington
By Ismail Farooq · Updated 2026-10-30
How most homes heat: Electric baseboard heaters, heat pumps and gas furnaces.
Western Washington is a marine climate: mild, wet winters and dry summers that have grown hotter. Cheap hydropower made electric baseboard heaters common, especially in older homes and apartments; they need line-voltage thermostats. Heat pumps work very well around Seattle and rarely need aux heat.
Eastern Washington, around Spokane and Yakima, has cold winters and hot, dry summers. Heat pumps there need sensible lockouts, and dual fuel with a gas furnace is common.
Climate zones in Washington
| Place | IECC zone |
|---|---|
| Seattle | 4C |
| Tacoma | 4C |
| Olympia | 4C |
| Spokane | 5B |
| Yakima | 5B |
Zones follow county lines on the 2021 IECC map, and some counties changed zone between code editions. DOE’s Building America climate zone map lists every county.
Starting settings
- Everyday setpoints: about 68 °F in winter and 78 °F in summer while you’re home, set back while you sleep or are out (DOE’s guidance).
- Gas, oil or propane furnace or boiler: setbacks of 7 to 10 °F are fine; use the thermostat’s early-start feature so the house is warm on time.
- Heat pump: keep winter setbacks small (2 to 4 °F) so a cold morning doesn’t bring on aux heat.
- Dry air: a higher cooling setpoint still feels comfortable, and winter air gets very dry. A whole-house humidifier wired to the thermostat should aim for about 30–40%, lower in very cold weather.
- Marine (mild) areas: heat pumps rarely need aux heat, and many homes need little cooling.
- Freeze protection: keep the away or minimum temperature at about 55 °F or higher in winter, and make sure the thermostat keeps working without Wi-Fi.
Heat pump lockouts for Washington
If you have a heat pump, these are starting points for the outdoor temperatures that control backup heat. Your installer’s balance point is better if you have it.
| Zone | Aux heat lockout (electric strips) | Compressor lockout (dual fuel) |
|---|---|---|
| 4 | 30–35 °F | Around 25–35 °F |
| 5 | 25–35 °F for a standard heat pump; lower for a cold-climate model | Around 20–35 °F |
| 6–8 | From the heat pump’s rated output at low temperatures; cold-climate models often run well below 10 °F | Often 0–25 °F, from the installer’s balance point |
Rebates
Many utilities give rebates or bill credits for smart thermostats, sometimes in return for joining a peak-day program. Programs change often, so check your electric and gas utility’s website, or search by ZIP code in the ENERGY STAR rebate finder.