A heat pump needs a thermostat that switches its reversing valve on the O/B wire and brings on backup heat when the heat pump falls behind. EIA's 2020 survey counted 16.13 million U.S. homes heated mainly by a heat pump. Every thermostat here has a maker statement of heat pump support.
Support comes in degrees: count your compressor stages (Y, Y2) and your backup heat (AUX/W2, E), and match them to each maker's stage statement. Auxiliary heat controls matter too, because resistance backup heat costs far more to run than the heat pump itself.
ENERGY STAR labels smart thermostats on field data from real homes: at least 8% less heating and 10% less cooling run time, with an average saving EPA puts at about 8% of heating and cooling bills. The label matters less than the fit: a thermostat that can't run your system saves nothing.
Honeywell Home RTH9585WF1004/W Smart Thermostat
On power, its maker says it needs a C wire ("C-Wire required"). Its maker states heat pump support. Systems: COMPATIBLE WITH: Forced air (gas, oil or electric), hot water and steam, and heat pumps with electric backup. It touch Screen, Voice. Power: AC Power Supply. Its listing shows 20,133 buyer reviews. It suits phone control and scheduling and heat pump systems. Where it gives ground: needs a C wire (maker); needs Wi-Fi for smart features. Warranty: 1 year warranty.
Honeywell Home RTH9600WF Smart Thermostat
On power, its maker says it needs a C wire ("c-wire required"). Its maker states heat pump support. Systems: COMPATIBLE WITH: Forced air (gas, oil or electric), hot water and steam, and heat pumps with electric backup. It amazon Alexa, Android, Google Assistant, IFTTT, iOS. Power: Battery Powered. Its listing shows 20,133 buyer reviews. It suits phone control and scheduling and heat pump systems. Where it gives ground: needs a C wire (maker); needs Wi-Fi for smart features. Warranty: 2 year limited warranty.
Honeywell Home RTH6580WF Smart Thermostat
On power, its maker says it needs a C wire ("C-Wire required"). Its maker states heat pump support. Systems: COMPATIBLE WITH: Forced air (gas, oil or electric), hot water and steam, and heat pumps with electric backup. It amazon Alexa, Google Assistant, Vera. Power: Corded Electric. Its listing shows 15,556 buyer reviews. It suits phone control and scheduling and heat pump systems. Where it gives ground: needs a C wire (maker); needs Wi-Fi for smart features. Warranty: Warranty.
Honeywell Home RCHT8610WF2006/W Smart Thermostat
On power, its maker says it needs a C wire ("C-Wire required"). Its maker states heat pump support. Systems: COMPATIBLE WITH: Forced air (gas, oil or electric), hot water and steam, and heat pumps with electric backup. It amazon Alexa, Apple HomeKit, Google Assistant. Power: Electric. Its listing shows 4,491 buyer reviews. It suits phone control and scheduling and heat pump systems. Where it gives ground: needs a C wire (maker); needs Wi-Fi for smart features. Warranty: 2 year limited warranty.
Aqara W200 Smart Thermostat
On power, the listing does not say whether it needs a C wire. Its maker states heat pump support. Systems: works with about 85% of HVAC systems, including furnaces, air conditioners, heat pumps, boilers, and PTAC unit. It apple HomeKit. Power: Corded Electric. Its listing shows 258 buyer reviews. It suits phone control and scheduling and heat pump systems. Where it gives ground: c-wire need not stated; needs Wi-Fi for smart features.
The ranking in one table
| Model | C wire | Heat pump | Stages | Sensors |
|---|---|---|---|---|
| Honeywell Home RTH9585WF1004/W Smart Thermostat | C-Wire required | Forced air (gas, oil or electric), hot water and | Not stated | Not stated |
| Honeywell Home RTH9600WF Smart Thermostat | c-wire required | Forced air (gas, oil or electric), hot water and | Not stated | Not stated |
| Honeywell Home RTH6580WF Smart Thermostat | C-Wire required | Forced air (gas, oil or electric), hot water and | Not stated | Not stated |
| Honeywell Home RCHT8610WF2006/W Smart Thermostat | C-Wire required | Forced air (gas, oil or electric), hot water and | Not stated | Not stated |
| Aqara W200 Smart Thermostat | No C-wire | with about 85% of HVAC systems, including furnac | Not stated | Not stated |
How to choose
Start behind the old thermostat: note every terminal letter with a wire in it. A C wire settles power; O/B means heat pump; W2 or Y2 means a second stage. Then read each maker's statements on exactly those points before features like screens, voice assistants or sensors.
Where a listing is silent on something your system needs, treat it as unconfirmed and use the maker's online checker. Keep the old thermostat's wiring photo until the new one has run heating, cooling and fan.
When another list fits better
For furnaces and boilers, heat pump support is irrelevant; the full smart thermostat table has more choices.
Questions shoppers ask
Do I need a special thermostat for a heat pump?
What does aux heat mean?
Will any smart thermostat work with a heat pump?
How much does a smart thermostat save?
How do I check compatibility?
Our editors choose and order the picks from the makers' own statements; every pick meets the rule printed above. How we read a thermostat · Affiliate disclosure