Best smart thermostat: Google Nest Learning Thermostat (4th Gen)
Google lists the 4th-gen Learning Thermostat as compatible with single- and two-stage heat pumps, with or without AUX heat, and with dual-fuel systems that pair a heat pump with a furnace (Google’s compatibility chart). Its Heat Pump Balance setting checks the weather near your home and only starts AUX heat when it’s colder outside than a lockout temperature, with Max Comfort, Balanced and Max Savings options. A remote temperature sensor comes in the box. Google recommends a professional install for dual-fuel systems.
- Learns your schedule automatically
- Matter brings it to Apple Home and Alexa
- Remote temperature sensor included
- One of the most expensive thermostats
- The remote sensor doesn’t appear in Apple Home or Matter
Skip it if you rent, or your heating system isn’t compatible. Check Google’s compatibility tool before buying.
Best for fine-tuning a heat pump: ecobee Smart Thermostat Enhanced
ecobee rates the Enhanced for heat pumps with two compressor stages plus one stage of AUX heat (ecobee). ecobee’s threshold settings include the lowest outdoor temperature the compressor will run at and the highest at which AUX heat may run, which is how you keep expensive backup heat off on mild days. It has a radar occupancy sensor and comes with a Power Extender Kit for homes without a C-wire. If your system has two stages of backup heat, the ecobee Premium supports two AUX stages and includes a room sensor, for about $260.
- Heat pumps with two compressor stages plus one AUX stage (maker)
- Threshold settings limit the compressor and AUX heat by outdoor temperature
- Radar occupancy sensor; Power Extender Kit in the box
- No room sensor in the box
- One AUX stage: two-stage backup heat needs the Premium
Skip it if you have a variable-speed (inverter) heat pump. Many need the maker’s own control or an adapter.
Nest looks for less: Google Nest Thermostat
The cheaper Nest Thermostat supports single-stage heat pumps with or without AUX heat, and single-stage dual fuel, but not two-stage heat pumps. With a heat pump it needs a C-wire or the Nest Power Connector. It offers Heat Pump Balance too. Check that your heat pump is single-stage before buying: the model number on the outdoor unit or your installer’s paperwork will tell you.
- Matter support, so it works in Apple Home too
- Clean design, easy install
- Frequent sales
- Doesn’t learn your schedule on its own
- No remote room sensors
Skip it if your home has hot and cold rooms that need remote sensors.
Best for ductless mini-splits: Mysa Smart Thermostat for Mini-Splits
Ductless mini-splits are run by an infrared remote, not wall wiring, so a wired smart thermostat won’t work. Mysa’s controller learns your remote’s signals and adds schedules, geofencing and control from Apple Home, Alexa or Google Assistant, with no subscription. It needs a clear line of sight to the indoor unit, up to about 25–30 feet away (Mysa help), and a nearby outlet.
- Works with most mini-splits that use an IR remote (maker)
- No subscription; works with Apple Home, Alexa and Google Assistant
- 5-year warranty and 30-day trial (maker)
- Needs a clear line of sight to the indoor unit
- Plug-in only, so it needs a nearby outlet
Skip it if your heat pump is ducted and has a wall thermostat. A wired smart thermostat is the right tool.
Before you buy
Five checks that save a return:
- 1Photograph your current thermostat’s wires and labels.
- 2Find out whether your heat pump is single-stage, two-stage or variable-speed (inverter).
- 3Variable-speed: ecobee says modern cold-climate heat pumps need an adapter to work with smart thermostats, including its own (ecobee).
- 4Dual fuel (a heat pump plus a gas furnace): Google recommends a professional install.
- 5Run the maker’s compatibility checker before you order.
AUX heat vs emergency heat
AUX heat is backup heat your thermostat turns on by itself when the heat pump can’t keep up. Emergency heat is backup heat you switch on manually when the heat pump isn’t working. Google notes that running emergency heat is usually expensive and inefficient, and that needing it regularly may mean your system needs servicing (Google Nest Help).
For what a smart thermostat can save, see do smart thermostats save money?, and for the budget models side by side, ecobee vs Nest vs Amazon.
Where these facts come from
We haven’t installed these on our own heat pumps. Compatibility comes from the makers’ own documentation, checked on September 29, 2026:
