Smart Thermostats for Heat Pumps: What They Save and Which to Buy
ENERGY STAR says its certified smart thermostats save about 8% of heating and cooling bills on average, about $50 a year. A heat pump needs one that suits it: the Department of Energy says not to set a heat pump back by hand if that brings on its backup electric-resistance heat, which costs more, and to use a smart or programmable thermostat with functions suitable for a heat pump. ENERGY STAR adds that variable-speed heat pumps generally work best with the thermostat their maker recommends. Our picks, all ENERGY STAR certified: the Honeywell Home T9 (its listing names heat pumps with electric backup), the Google Nest Learning Thermostat (4th gen) (no C-wire needed in most homes) and the ecobee Smart Thermostat Essential for a heat pump with a gas furnace. For a ductless mini-split, a Wi-Fi controller such as the Cielo Breez Max; none of those is certified.
- ENERGY STAR
- Room sensor included
- ENERGY STAR
- Dual fuel
- Mini-split, window or portable AC
- Wi-Fi
Most thermostat reviews rate apps and screens. This guide starts from what matters with a heat pump: which thermostat suits your kind of system, whether it needs a C-wire, and what it saves at your state’s electricity price. Every pick’s model number is checked against ENERGY STAR’s list of 120 certified smart thermostats.
Why a heat pump needs the right thermostat
A heat pump is the most efficient form of electric heating: the Department of Energy (DOE) says it provides up to three times more heat than the energy it uses. Many ducted heat pumps also have backup electric-resistance heat, often called auxiliary heat, which can come on when the heat pump falls behind, for example after a setback. DOE says that backup heat costs more to run.
This is where an ordinary setback goes wrong. DOE says you can save as much as 10% a year on heating and cooling by turning the thermostat down 7°F to 10°F for 8 hours a day, but adds: if you have a heat pump, don’t do this without a smart or programmable thermostat designed for heat pumps. Its heat pump advice is direct: do not set the thermostat back by hand if it causes the backup electric-resistance heat to come on.
ENERGY STAR checks this too. To be certified, a smart thermostat maker has to report how much electric resistance heat its heat pump customers use, by outdoor temperature from 0°F to 60°F, alongside the run-time savings every certified model must show.
Which thermostat for which heat pump
| Your heat pump | What to buy |
|---|---|
| Ducted, one or two speeds | An ENERGY STAR certified smart thermostat whose listing or maker names heat pumps with auxiliary (backup) heat |
| Ducted, variable speed | The thermostat your heat pump’s maker recommends: ENERGY STAR says these systems generally perform best with it, certified or not |
| With a gas furnace (dual fuel) | A certified thermostat whose listing names dual fuel |
| Ductless mini-split | A Wi-Fi controller for the mini-split’s infrared remote; none is ENERGY STAR certified |
Before buying, check the thermostat against your wiring: ecobee and Google both have online compatibility checkers. Heat pump wiring can include a reversing-valve wire (O/B) and auxiliary heat wires (W1, W2); the Cielo listing below names both.
Heating with a furnace, boiler or baseboard heaters instead? Our guide to the best smart thermostats covers every kind of heating, with what one saves on your fuel in your state.
What it saves
ENERGY STAR’s figure is about 8% of heating and cooling bills, or $50 a year, on average. The picker applies the 8% to your heating cost, starting from what homes that heat with electricity use in your state in the government’s household survey, and to your cooling cost if you add it.
| State | Electric heating | Cost a year | 8% saving |
|---|---|---|---|
| Florida | 1,533 kWh | $234 | $19 |
| Texas | 2,237 kWh | $359 | $29 |
| US average | 2,484 kWh | $452 | $36 |
| North Carolina | 2,861 kWh | $427 | $34 |
| Minnesota | 3,050 kWh | $496 | $40 |
| Ohio | 3,437 kWh | $643 | $51 |
| Pennsylvania | 3,362 kWh | $707 | $57 |
| Washington | 4,254 kWh | $613 | $49 |
The survey averages every home that heats with electricity, heat pumps and electric resistance together, and DOE says a heat pump uses about half the electricity of electric furnaces or baseboard heaters for heating. So if you know your own heating cost, type it into the picker. Cooling adds to the saving: put in what summer adds to your bill.
The C-wire question
Many smart thermostats need constant power from a common wire (C-wire). With a heat pump this can matter more: Google says its Nest Thermostat needs a C-wire or a power accessory on heat pump systems, and Sensi says the same for the Sensi Lite. What each pick’s listing says:
| Thermostat | C-wire |
|---|---|
| Google Nest Learning Thermostat (4th gen) | Not required in most homes |
| ecobee Smart Thermostat Premium | Power Extender Kit included for homes without one |
| ecobee Smart Thermostat Essential | Power Extender Kit sold separately |
| Honeywell Home T9 | Power adapter included as an alternative |
| Cielo Smart Thermostat Eco | C-wire adapter included |
| Mysa Smart Thermostat for Central HVAC | Required, sold separately |
| Amazon Smart Thermostat | Required |
Our picks
Every thermostat here is on ENERGY STAR’s list of certified smart thermostats under the model number on its listing (checked 7 October 2026), except the mini-split controller, and was in stock that day. Features are from each listing’s own description.
| Best for | Pick | Key spec | Amazon |
|---|---|---|---|
| Best for most heat pumps | Honeywell Home T9 smart thermostat with room sensor | ENERGY STAR · Room sensor included | Check price |
| No C-wire in most homes | Google Nest Learning Thermostat (4th gen) | ENERGY STAR · Temperature sensor included | Check price |
| Dual fuel | ecobee Smart Thermostat Essential | ENERGY STAR · Dual fuel | Check price |
| Two auxiliary heat stages | Cielo Smart Thermostat Eco | ENERGY STAR · C-wire adapter included | Check price |
| Heat pumps with or without aux heat | Mysa Smart Thermostat for Central HVAC | ENERGY STAR · Needs a C-wire | Check price |
| Room sensor, C-wire kit | ecobee Smart Thermostat Premium | ENERGY STAR · C-wire kit included | Check price |
| Simple, works with Alexa | Amazon Smart Thermostat | ENERGY STAR · Needs a C-wire | Check price |
| Ductless mini-splits | Cielo Breez Max mini-split controller | Mini-split, window or portable AC | Check price |
- ENERGY STAR
- Room sensor included
- ENERGY STAR
- Temperature sensor included
- ENERGY STAR
- Dual fuel
- ENERGY STAR
- C-wire adapter included
- ENERGY STAR
- Needs a C-wire
- ENERGY STAR
- C-wire kit included
- ENERGY STAR
- Needs a C-wire
- Mini-split, window or portable AC
- Wi-Fi
How these were chosen
We downloaded ENERGY STAR’s list of certified smart thermostats (120 models, 7 October 2026) and kept Amazon listings from established brands whose model number is on it and whose listing says how it works with a heat pump or a C-wire, in stock on 7 October 2026. The mini-split controller is the exception, because ENERGY STAR certifies none. Savings use ENERGY STAR’s average for certified smart thermostats; heating costs use EIA’s 2020 household survey (electric space heating per home that heats with electricity, by state) and EIA residential electricity prices for January to July 2026. Heat pump advice is from DOE’s Energy Saver guide and ENERGY STAR’s smart thermostat pages.
Sources
- ENERGY STAR, certified smart thermostats (Product Finder)
- ENERGY STAR, Smart Thermostats
- U.S. Department of Energy, Energy Saver: Programmable Thermostats (archived copy)
- U.S. Department of Energy, Energy Saver: Heat Pump Systems (archived copy)
- U.S. Energy Information Administration, 2020 Residential Energy Consumption Survey (RECS)
- U.S. Energy Information Administration, Electric Power Monthly, Table 5.6.B: average residential electricity price by state, January to July 2026 (year to date)
How we pick products for every buying guide: our buying guide standards.
Frequently asked questions
Many do: six of our seven certified picks name heat pumps on their listings. Check the wiring first, since heat pump wiring can include a reversing-valve wire and auxiliary heat wires, and some thermostats need a C-wire on a heat pump. Variable-speed heat pumps generally work best with the thermostat their maker recommends, according to ENERGY STAR.
Only with a thermostat made for heat pumps. DOE says not to set a heat pump back by hand if it brings on the backup electric-resistance heat, which costs more to run.
Backup electric-resistance heat that can come on when the heat pump falls behind, for example after a setback. DOE says it costs more to run, which is why ENERGY STAR makes thermostat makers report how much of it their heat pump customers use.
ENERGY STAR says certified smart thermostats save about 8% of heating and cooling bills on average, about $50 a year. For the average home that heats with electricity, 8% of the heating alone is about $36 a year at US average prices; cooling adds to that.
A Wi-Fi controller can, by sending the mini-split’s infrared remote signals; Cielo says its Breez Max works with mini-splits that have an infrared remote. None of these controllers is ENERGY STAR certified.