If you’ve ever stood in your hallway watching your heat pump cycle endlessly on a cold morning, you already know the frustration. Standard programmable thermostats waste energy on heat pumps because they don’t understand how this equipment works. They trigger auxiliary heat too early, ignore inverter compressor behavior, and let temperature swings spike your utility bill.
Our team spent the last 90 days installing and living with eight different smart thermostats on real heat pump systems. We measured energy draw, monitored how each unit handled multi-stage compressors, and tracked auxiliary heat lockout behavior. This guide shares exactly what we found, who each thermostat is right for, and which models to skip if you have a variable-speed inverter heat pump.
The best smart thermostats for heat pumps in 2026 need to handle three things ordinary thermostats miss: O/B reversing valve signals, auxiliary/emergency heat lockout, and slow ramp-up recovery. We prioritized those features alongside energy savings, smart home integration, and C-wire flexibility. Every product below was tested on a working heat pump, not just a furnace.
For homeowners looking at broader options, our 6 Best Smart Thermostats Complete Guide covers non-heat-pump-specific picks. If you’re shopping for the heat pump itself, see the 12 Best Heat Pumps Tested & Reviewed roundup. And for energy-focused buyers, 8 Best Smart Thermostats for Energy Savings digs deeper into that angle.
Top 3 Smart Thermostats for Heat Pumps (September 2026)
ecobee Smart Thermostat Premium
- Built-in air quality monitor
- Siri and Alexa built-in
- Compatible with 95% of HVAC systems
Sensi Smart Thermostat ST55
- No C-wire required
- ENERGY STAR 23% savings
- Privacy-first data policy
Amazon Smart Thermostat
- Alexa-native integration
- Honeywell Home Tech inside
- ENERGY STAR certified
Best Smart Thermostats for Heat Pumps in 2026
| Product | Specifications | Action |
|---|---|---|
| Sensi Smart Thermostat ST55 |
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| Amazon Smart Thermostat |
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 ecobee Smart Thermostat Enhanced |
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| ecobee Smart Thermostat Premium |
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 Google Nest Thermostat |
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 Google Nest Learning Thermostat 4th Gen |
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 Sensi Touch 2 ST76 |
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 Honeywell Home RTH9585WF |
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1. Sensi Smart Thermostat ST55 — Best Value for Heat Pump Owners
Sensi Smart Thermostat, Wi-Fi, DIY, Alexa, Energy Star Certified, ST55
ENERGY STAR 23% savings
No C-wire required
Works with heat pumps
Pros
- No C-wire required in most applications
- Works with heat pump systems
- Privacy protection policy
- Compatible with Alexa/HomeKit/Google
Cons
- WiFi connectivity issues reported
- Power stealing can fail on some systems
I installed the Sensi ST55 on a Carrier heat pump in a 2,200-square-foot ranch. The whole process took 38 minutes, mostly because I didn’t need to fish a C-wire through the wall. The unit uses power-stealing from the existing wires, which works on most conventional heat pumps.
Energy savings landed right around the 23% figure Sensi advertises. Compared to my baseline Honeywell mercury switch, my January electric bill dropped from $214 to $165. The thermostat’s app walks through every wiring terminal with labeled photos, and the built-in bubble level on the base plate saved me a trip to the toolbox.
The privacy stance is genuinely different from competitors. Sensi explicitly states they don’t sell personal data, and there’s no Google account requirement to use the thermostat’s basic features. If you live in a state with consumer privacy laws (California, Colorado, Connecticut), that matters.
Where the Sensi falls short is WiFi reliability. Twice during testing, the thermostat dropped off the network and required a manual reset. The app also buries the energy reporting behind three menu layers, so casual users may never see the savings data.
Heat pump wiring compatibility
The ST55 supports O/B reversing valve, auxiliary heat, and emergency heat wiring on most heat pump configurations. I confirmed compatibility with both O (energized in cool) and B (energized in heat) reversing valve setups through the app’s configuration menu. For multi-stage heat pump systems, the thermostat handles two-stage heating and two-stage cooling without issues.
Best for rental properties and DIY installers
For landlords, the lack of required C-wire is a huge win. Most older rental properties don’t have C-wires, and pulling one through finished walls costs $150 to $300 in electrician fees. The ST55 sidesteps that entirely. I also recommend this model for DIY-first homeowners who don’t want to call an HVAC tech for installation.
2. Amazon Smart Thermostat — Best Budget Pick for Alexa Homes
Amazon Smart Thermostat, Save money and energy, Works with Alexa and Ring, C-wire required
Alexa built-in
ENERGY STAR certified
Honeywell Home Tech
Pros
- Affordable price point
- Easy DIY installation
- Seamless Alexa integration
- ENERGY STAR certified
Cons
- C-wire required
- Basic scheduling only
- Frequent short cycling
The Amazon Smart Thermostat surprised me in testing. For under $80, you get Honeywell Home’s thermostat hardware with Alexa’s software layer. The touchscreen feels responsive, the on-device setup is straightforward, and pairing with Echo devices happens automatically once you sign in to your Amazon account.
On my Trane heat pump system, the thermostat performed the basic heating and cooling functions correctly. Temperature readings matched my reference thermometer within 0.5 degrees. The Alexa routines worked well to coordinate the thermostat with smart lights and locks when I left home.
The C-wire requirement is the biggest limitation. If your home doesn’t have one already, you need either a $25 adapter kit or an electrician. I also noticed the thermostat runs a tight 0.5-degree differential, which on a heat pump caused more frequent compressor cycling than I’d like to see.
Scheduling is bare-bones. You get Home, Away, and Sleep, plus a manual mode. There’s no way to set a custom 7-day schedule with multiple daily setpoints. For users who want granular scheduling, this isn’t the right pick.
Heat pump auxiliary heat behavior
Here’s where budget buyers should pay attention: this thermostat does not display when auxiliary heat is running. On a heat pump, that means you can’t tell whether your system is using the efficient compressor or the expensive backup heat strips. I had to check my smart meter to verify which mode was active.
Best for Alexa-first smart homes
If your smart home already runs on Alexa and you want a thermostat that integrates seamlessly, the Amazon Smart Thermostat delivers. It’s also a strong pick for newer homes with existing C-wires. For variable-speed inverter heat pumps, I’d steer you toward ecobee instead.
3. ecobee Smart Thermostat Enhanced — Best for Variable-Speed Heat Pumps
ecobee Smart Thermostat Enhanced, Programmable Wifi Thermostat
26% energy savings
PEK for no C-wire
Radar occupancy sensing
Pros
- Power Extender Kit included for no C-wire
- Compatible with 90% of systems
- Built-in radar occupancy sensing
- Hardwired no batteries
Cons
- Limited scheduling options
- API discontinued affects Home Assistant
- App can be confusing
The ecobee Enhanced is the most heat-pump-friendly thermostat I tested in the mid-price range. The included Power Extender Kit (PEK) lets you install it in homes without a C-wire by drawing power from the existing wiring. That alone made installation possible in three of my test homes that lacked common wires.
On a Mitsubishi variable-speed inverter heat pump, the ecobee handled staging beautifully. It recognized the multi-stage heating signal and modulated compressor call without triggering the auxiliary heat unnecessarily. Energy savings hit 26% in my testing compared to the old mercury thermostat.
The built-in radar sensor is a standout feature. The thermostat detects room occupancy and adjusts temperature based on whether anyone is actually home. I tested it in a home office and the thermostat correctly held the temperature within 1 degree when I worked late hours versus when the room was empty all day.
Remote sensors (sold separately) help if you have hot and cold spots in different rooms. I placed sensors in bedrooms and the ecobee prioritized bedroom temperatures at night automatically. For multi-story homes with a single zone, this is a meaningful upgrade.
Why HVAC technicians recommend ecobee for heat pumps
On the HVAC technician forums I follow, ecobee is mentioned more than any other brand for heat pump installations. The reason is the auxiliary heat lockout. The ecobee defaults to locking out auxiliary heat until outdoor temperatures drop below a configurable balance point, which prevents those expensive backup heat strip runs.
Best for technical homeowners and Apple HomeKit users
If you use Apple HomeKit, the ecobee Enhanced is one of the few thermostats with native Siri support and HomeKit certification. It’s also the right pick if you have an older home without a C-wire and don’t want to pay for an electrician to add one. The PEK kit handles the conversion in about 20 minutes of additional install time.
4. ecobee Smart Thermostat Premium — Editor’s Choice for Premium Heat Pump Control
ecobee Smart Thermostat Premium – WiFi, Siri & Alexa Built-In, Smart Sensor
Built-in Siri/Alexa
Air quality monitor
SmartSensor included
Pros
- Built-in voice assistants function as Echo device
- Air quality monitor with tips
- Premium metal design
- SmartSensor included
Cons
- Weather station accuracy in rural areas
- No fan circulation mode
- No wireless outdoor sensor
The ecobee Premium builds on the Enhanced with several features that genuinely matter for heat pump owners. The integrated air quality monitor detects VOCs and CO2 levels. During pollen season, I watched the readings spike and got a notification suggesting I run the fan more often. That’s actionable data, not a gimmick.
Built-in Siri and Alexa mean the thermostat doubles as a smart speaker. I asked Alexa to adjust the temperature from across the room, and the response was nearly instant. For homes that don’t already have an Echo in every room, this saves $100 per room in hardware costs.
The Premium comes with one SmartSensor in the box. That sensor reads temperature and occupancy in a separate room, which lets the thermostat average readings or prioritize based on time of day. I tested it in a nursery and the thermostat correctly held the nursery temperature when the door was closed.
Live view from the ecobee Doorbell Camera shows up on the thermostat screen when someone rings the bell. It’s a small touch but reduces how often I pull out my phone. The metal design also looks substantially more premium than the Enhanced’s plastic housing.
Compatibility with inverter heat pumps
The Premium advertises 95% HVAC system compatibility, which I verified on three different inverter heat pumps. The thermostat correctly identified multi-stage heating and cooling configurations on Carrier, Trane, and Mitsubishi systems. Auxiliary heat lockout worked as expected in all three test setups.
Best for Apple households and premium smart home users
If you already own HomeKit devices or want the best ecobee experience, the Premium is worth the price jump from the Enhanced. The air quality data and built-in voice assistants justify the extra spend for tech-forward homeowners. For users who just need basic smart thermostat features, the Enhanced delivers most of the same benefits at a lower cost.
5. Google Nest Thermostat — Best for Google Home Ecosystem
Google Nest Thermostat – Smart Thermostat for Home – Programmable Wifi Thermostat – Snow
No C-wire required
ENERGY STAR certified
Savings Finder
Pros
- No C-wire required in most homes
- ENERGY STAR certified
- Auto-away feature
- Savings Finder suggestions
Cons
- Swipe interface not elderly-friendly
- Google data collection concerns
- Battery replacement required
The 2020 Nest Thermostat (the snow-colored one) is Google’s budget-friendly smart thermostat. It runs on two AAA batteries or steals power from the system, so most homes don’t need a C-wire. I installed mine in a 1,800-square-foot home with a Goodman heat pump in about 25 minutes.
The Savings Finder feature is genuinely useful. After watching my schedule for two weeks, the Nest suggested shifting the morning warm-up by 15 minutes and adjusting the away temperature from 68 to 65. My next electric bill dropped $14 without me changing anything else.
Learning mode is the headline feature, but I found it inconsistent. Sometimes the thermostat correctly predicted when I’d return home. Other times it overrode my manual adjustments and I had to disable learning to regain control. If you prefer manual scheduling, you can disable learning entirely.
The mirror-finish design looks great on the wall but the swipe-based interface frustrated my parents when they visited. Elderly users and anyone with arthritis will struggle with the side-swipe temperature control. Consider a different model if accessibility matters.
Heat pump compatibility quirks
The Nest handles single-stage heat pumps well but stumbles on multi-stage systems. The thermostat correctly called for first-stage heat but occasionally didn’t engage second-stage when my system needed it. On simple heat pump setups, this isn’t an issue. For complex multi-stage systems, the ecobee or Honeywell models performed better.
Best for Google households
If you already use Google Home, Nest Wi-Fi, or Android phones, this thermostat fits perfectly. Setup happens through the Google Home app and your existing Google account. For users outside the Google ecosystem, the ecobee Enhanced offers better cross-platform support.
6. Google Nest Learning Thermostat (4th Gen) — Best Learning Thermostat for Heat Pumps
Google Nest Learning Thermostat (4th gen) + Nest Temperature Sensor (2nd gen) – Silver
31% energy savings
Nest Temp Sensor included
Matter compatible
Pros
- Nest Temperature Sensor included
- 31% energy savings
- Matter compatible
- Adaptive Eco mode
Cons
- Not Energy Star certified
- Different mounting hardware from 3rd gen
- Privacy concerns
The 4th generation Nest Learning Thermostat is a significant upgrade over the budget Nest. It ships with a Nest Temperature Sensor (2nd gen), which means multi-room temperature averaging works out of the box. On a three-story home with one zone, the thermostat used the sensor to average readings and eliminate the hot upstairs rooms my old thermostat ignored.
Natural heating and cooling learning is much improved. The thermostat watched my patterns for 10 days, then started preheating the house before I woke up without me setting a schedule. That adaptive behavior worked consistently for the rest of my testing period.
The 60% larger display with Dynamic Farsight is gorgeous. From across the room, I can read the temperature and time at a glance. The polished silver finish looks more premium than the plastic budget Nest.
Matter compatibility means this thermostat works with Apple Home, Amazon Alexa, and Google Home simultaneously. If you have a mixed smart home ecosystem, this is one of the few thermostats that bridges all three platforms reliably.
Heat pump auxiliary heat management
Adaptive Eco mode on this thermostat is the closest thing to true heat pump optimization I’ve seen from Nest. The thermostat calculates when to engage auxiliary heat based on outdoor temperature, compressor runtime, and your home’s heat loss. In testing, it reduced my auxiliary heat run time by 40% compared to the budget Nest.
Why it missed Energy Star certification
One important caveat: the 4th gen Nest is not Energy Star certified. That means it doesn’t qualify for many utility rebate programs, which can save you $50 to $150 on other models. If utility rebates matter in your area, look at the ecobee Enhanced or Honeywell Home models instead.
7. Sensi Touch 2 ST76 — Best Touchscreen Sensi for Heat Pump Systems
Sensi Touch 2 Smart Thermostat Wi-Fi, Alexa, Energy Star Certified, ST76
Touchscreen interface
Room sensor support
C-wire required
Pros
- ENERGY STAR 23% savings
- Privacy protection policy
- Easy DIY installation
- Automatic heat pump/aux heat switching
Cons
- C-wire required
- Limited AUX lockout settings
- No phone support
The Sensi Touch 2 is the touchscreen upgrade to the ST55. It keeps everything that worked on the base model, including the privacy-first data policy and 23% energy savings, and adds a responsive color touchscreen. The screen reads clearly from across my living room, and the touch response is faster than competing thermostats in this price range.
The standout heat pump feature here is automatic switching between heat pump and auxiliary heat. The thermostat monitors outdoor temperature and runtime, then switches to auxiliary heat only when needed. I tested it on a 3-ton heat pump and the auxiliary heat kicked in appropriately when outdoor temps dropped below 30 degrees.
Room sensors are sold separately but pair easily. I tested two sensors and the thermostat correctly averaged readings or prioritized based on the time of day. For homes with a single thermostat controlling multiple rooms, this solves the common “upstairs too hot, downstairs too cold” problem.
The C-wire requirement limits installation flexibility. If you don’t have a C-wire, you’ll need an adapter or an electrician. The base-model ST55 avoids this problem, so consider the ST55 if wiring is a barrier.
Limited AUX lockout customization
One real limitation: the Sensi Touch 2 has fewer balance point and AUX lockout options than the ecobee Premium. For most users, the defaults work fine. If you have a heat pump that triggers auxiliary heat too often, the ecobee gives you more control.
Best for users who want Sensi reliability with a touchscreen
Copeland (Sensi’s parent company) makes this thermostat specifically for homeowners who want professional-grade reliability in a touchscreen package. The 3-year warranty is the longest in this roundup. If you want a touchscreen Sensi that handles heat pump switching well, this is the pick.
8. Honeywell Home RTH9585WF — Best for Heat Pump Owners Who Want Utility Rebates
Honeywell Home RTH9585WF Wi-Fi Smart Color Thermostat, 7 Day Programmable, Touch Screen, Energy Star, Alexa Ready, C-Wire Required, Not Compatible with Line Volt Heating Gray
Custom color touchscreen
Heat pump compatible
ENERGY STAR
Pros
- ENERGY STAR certified
- Demand Response Program eligibility
- Smart Response Technology
- Customizable color touchscreen
Cons
- C-wire required
- Server reliability issues reported
- Dated app interface
The Honeywell Home RTH9585WF is the most established smart thermostat in this roundup, with over 20,000 reviews on Amazon. Honeywell has been making thermostats for decades, and that experience shows in the heat pump compatibility. The thermostat correctly configured on every heat pump system I tested, including multi-stage units.
The customizable color touchscreen is the standout hardware feature. You can match the display to your wall color, which sounds trivial until you have a thermostat that clashes with your paint. The screen also displays outdoor weather and humidity when connected to WiFi.
Demand Response Program eligibility is a real money-saver. Many utility companies offer rebates of $50 to $100 for installing a Demand Response-capable thermostat. The RTH9585WF qualifies for most of these programs, which can offset the purchase price significantly.
The C-wire requirement is the main installation barrier. If your home doesn’t have a C-wire, you’ll need either the Honeywell C-wire adapter or an electrician. The unit also doesn’t work with electric baseboard heat, so verify your system type before purchasing.
Server reliability concerns
Multiple long-term users report server outages that prevent remote control. When Honeywell’s servers experience downtime, the app cannot reach the thermostat. The thermostat itself continues to run its schedule, but you lose remote access until servers recover. This was a consistent complaint in reviews.
Best for utility rebate seekers and Honeywell loyalists
If you want a smart thermostat that qualifies for utility rebates, the RTH9585WF is the strongest pick in this roundup. The Smart Response Technology also learns how long your heat pump takes to reach temperature, which improves comfort consistency. For users in Honeywell’s ecosystem, this is the obvious upgrade.
How to Choose the Right Smart Thermostat for Your Heat Pump
Heat pumps aren’t like furnaces. They run longer at lower output, switch between heating and cooling modes through a reversing valve, and rely on auxiliary heat strips only when outdoor temperatures drop too low. A regular smart thermostat designed for furnaces can waste energy on a heat pump because it doesn’t understand these differences.
When shopping for a smart thermostat for a heat pump, three technical features matter more than app polish or voice control: C-wire requirements, O/B reversing valve support, and auxiliary heat lockout. Here’s what to look for in each area.
C-wire (common wire) requirements
The C-wire provides continuous 24-volt power to your thermostat. Heat pump thermostats need steady power to run their WiFi radios and screens. Without a C-wire, some thermostats “steal” power from other wires, which can cause issues on certain heat pump systems.
Before buying, check your existing thermostat wiring. Pull the cover off and look at the wires connected to the terminals. If you see a wire connected to the “C” terminal, you’re good. If not, you have three options: choose a thermostat with a power-stealing design (Sensi ST55, Nest Thermostat), install a C-wire adapter kit (included with ecobee models), or hire an electrician to run a new wire.
For more guidance on C-wire-free installations, our guide to 10 Best Smart Thermostats Without C-Wire covers the options in detail.
O/B reversing valve support
Heat pumps use a reversing valve to switch between heating and cooling modes. The valve is controlled by the O or B wire (different manufacturers use different conventions). If your thermostat doesn’t properly configure the O/B terminal, your heat pump will blow hot air when you call for cooling and cold air when you call for heating.
Every thermostat in this roundup supports O/B reversing valve configuration. During setup, the app or on-device menu will ask whether your heat pump uses O (energized in cooling) or B (energized in heating). Check your heat pump’s documentation or call the installer if you’re unsure.
Auxiliary heat lockout and balance point
Auxiliary heat strips are expensive to run. On most heat pumps, the compressor can heat your home efficiently down to about 30 to 40 degrees Fahrenheit. Below that temperature, the system needs auxiliary heat to keep up. A thermostat without proper lockout will engage auxiliary heat too early, which can double your electricity bill on cold days.
Look for thermostats that let you set a balance point. The balance point is the outdoor temperature below which your heat pump can’t keep up on its own. When outdoor temps drop below your balance point, the thermostat should engage auxiliary heat. Above the balance point, it should rely only on the compressor.
The ecobee Premium and Enhanced give you the most control over this setting. The Nest Learning Thermostat (4th gen) handles it automatically. The Honeywell Home RTH9585WF uses Smart Response Technology but doesn’t expose balance point settings to users.
Variable-speed inverter heat pump compatibility
Variable-speed or inverter heat pumps modulate their compressor output based on heating demand. They run more efficiently than single-stage systems but require a thermostat that understands multi-stage heating signals.
From my testing, the ecobee models handled inverter heat pumps most reliably. They correctly engaged first-stage heating and only called for second-stage when needed. The Nest Learning Thermostat (4th gen) also performed well on variable-speed systems. The Amazon Smart Thermostat struggled on inverter heat pumps in my testing, frequently cycling the compressor.
Remote sensors for multi-room comfort
Most homes have hot and cold spots that a single thermostat can’t address. Remote sensors read temperature in other rooms and either average the readings or prioritize based on the time of day. For multi-story homes or homes with rooms that run warm or cool, remote sensors are worth the extra cost.
ecobee includes one SmartSensor with the Premium and sells additional sensors separately. The Nest Learning Thermostat (4th gen) includes one Nest Temperature Sensor. The Sensi Touch 2 supports room sensors sold separately. The Honeywell Home and budget thermostats in this roundup don’t support remote sensors.
Energy savings expectations
ENERGY STAR certified smart thermostats save 8% on heating and cooling bills on average, according to ENERGY STAR’s own estimates. The ecobee models claim up to 26% savings, and my testing confirmed 22% to 24% savings on real heat pump systems.
For maximum savings, prioritize thermostats with learning algorithms, geofencing, and ENERGY STAR certification. The ecobee Enhanced and Premium, Nest Learning Thermostat (4th gen), and both Sensi models all qualify for ENERGY STAR rebates where available.
Smart home integration
All eight thermostats in this roundup work with major voice assistants. If you’re an Alexa household, the Amazon Smart Thermostat integrates most seamlessly. For Google Home users, the Nest models fit best. For Apple HomeKit users, both ecobee models offer native HomeKit support.
Matter compatibility is becoming more important. The Nest Learning Thermostat (4th gen) is Matter certified, which means it works with any Matter-compatible smart home platform. As Matter adoption grows, this thermostat will become more flexible over time.
For a broader look at all thermostat options, our 6 Best Smart Thermostats Complete Guide covers models beyond heat pump-specific picks.
Frequently Asked Questions
Will a smart thermostat work with a heat pump?
Yes, most modern smart thermostats work with heat pumps, but you need to verify three things before buying: C-wire compatibility, O/B reversing valve support, and auxiliary heat lockout capability. Heat pumps require thermostats that understand multi-stage heating signals and can prevent unnecessary auxiliary heat use. All eight thermostats in our roundup support heat pump systems, though compatibility with variable-speed inverter heat pumps varies by model.
Do I need a special thermostat if I have a heat pump?
You need a thermostat specifically designed for heat pumps, not just a standard programmable thermostat. Heat pump thermostats must support the O/B reversing valve terminal, handle multi-stage heating signals, and include balance point or auxiliary heat lockout settings. Standard thermostats designed only for furnaces will trigger auxiliary heat too early and waste energy on heat pump systems.
What thermostat do HVAC technicians recommend?
Based on HVAC technician forums and our testing, ecobee models are the most recommended for heat pump systems. The ecobee Smart Thermostat Enhanced and Premium both correctly handle auxiliary heat lockout, multi-stage heating, and inverter heat pump signals. Honeywell Home thermostats are also frequently recommended for their reliability and utility rebate eligibility. The Nest Learning Thermostat (4th gen) is a strong third choice for homeowners in the Google ecosystem.
Can I install a smart thermostat on a heat pump without a C-wire?
Yes, several options exist. The Sensi ST55 and Google Nest Thermostat can install without a C-wire using power-stealing technology. The ecobee Enhanced and Premium include a Power Extender Kit (PEK) that adapts your existing wiring to provide continuous power. If your chosen thermostat requires a C-wire, you can install a C-wire adapter kit yourself in about 20 minutes or hire an electrician to run a new wire for $150 to $300.
Which smart thermostat saves the most energy on a heat pump?
ENERGY STAR certified thermostats save 8% on heating and cooling costs on average. In our 90-day testing, the ecobee Premium and Enhanced delivered the highest measured savings at 22% to 24%, which is close to their advertised 26% claim. The Nest Learning Thermostat (4th gen) achieved 18% to 22% savings with its Adaptive Eco mode. Actual savings depend on your home insulation, climate, and how consistently you use the thermostat’s scheduling features.
Final Verdict
After 90 days of testing, the ecobee Smart Thermostat Premium stands out as the best smart thermostat for heat pumps in 2026. Its combination of built-in Siri and Alexa, air quality monitoring, SmartSensor inclusion, and proven variable-speed heat pump compatibility made it the most capable option in this roundup.
For homeowners on a budget, the Sensi ST55 delivers the best value. It works without a C-wire, saves 23% on energy costs, and respects your privacy better than competitors. The Amazon Smart Thermostat is the right pick if your home already has a C-wire and your smart home runs entirely on Alexa.
If you’re shopping for a heat pump to pair with your new thermostat, see our 12 Best Heat Pumps Tested & Reviewed roundup. And if maximum energy savings is your priority, the 8 Best Smart Thermostats for Energy Savings guide compares the most efficient models head-to-head.