Smart Thermostats
Best Indoor Thermostat (2026): Our 5 Picks Ranked
As an Amazon Associate we earn from qualifying purchases. Specs below come from each product's Amazon listing; we do not test products in person.
For indoor temperature control, the Google Nest Thermostat leads this list: it works without a C wire, offers phone app control and Google Assistant voice control, and carries ENERGY STAR certification. The Sensi Touch 2 follows with room sensor support and a 3-year warranty, while the Heagstat H701 suits single-stage systems that need no C wire.
Starting out? See the main guide: Best Smart Thermostat
Top picks at a glance
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Best OverallGoogle Nest Thermostat9.8 View on Amazon -
Runner-UpSensi Touch 2 Smart Thermostat Wi-Fi9.4 View on Amazon -
Also GreatLike-New Amazon Smart Thermostat9.3 View on Amazon -
9.2 View on Amazon -
9.2 View on Amazon
Compare the specs
Ranked on works without a c-wire, room sensor support, works with alexa / google, energy star, phone app control from each listing, plus how many buyers have rated it. A dash (—) means we could not confirm that figure from the listing.
| Pick | Works without a C-wire | Room sensor support | Works with Alexa / Google | ENERGY STAR | Phone app control | Weight | Warranty |
|---|---|---|---|---|---|---|---|
| 1. Google Nest Thermostat | Yes | — | Yes | Yes | Yes | 0.31 lb | 1-year |
| 2. Sensi Touch 2 Smart Thermostat Wi-Fi | — | Yes | Yes | Yes | Yes | 0.62 lb | 3-year |
| 3. Like-New Amazon Smart Thermostat | — | Yes | Yes | — | Yes | — | — |
| 4. Honeywell Home RTH7600D 7-Day Programmable Touchscreen Thermostat | — | — | — | — | — | 0.55 lb | 1-year |
| 5. Heagstat Non-Programmable Thermostat for Home Conventional Single-Stage | Yes | — | — | — | — | 0.4 lb | 2-year |
Google Nest Thermostat
It is designed to work without a C wire, adds Google Assistant voice control and phone app control, and carries ENERGY STAR certification.
- Works without a C-wire
- Works with Alexa / Google
- ENERGY STAR
- Phone app control
- 1-year warranty stated
Good for
- Buyers with no C wire who want app control
- Buyers who want Google Assistant voice control
Skip it if
- You want a warranty longer than 1 year
- You run a heat pump system with no C wire
It turns itself down when you leave, and it monitors heating and cooling systems with alerts and maintenance reminders. It has a touch control and an LCD display, runs on corded electric power with 2 AAA batteries included, and measures 1.07 inches deep by 3.31 inches wide by 3.31 inches high. The box holds a steel plate, mounting screws, and a documentation bundle, and it carries a 1-year warranty.
Sensi Touch 2 Smart Thermostat Wi-Fi
It pairs room sensor support with Alexa and Google Assistant voice control, phone app control, and a 3-year warranty.
- Room sensor support
- Works with Alexa / Google
- ENERGY STAR
- Phone app control
- 3-year warranty stated
Good for
- Buyers who want room sensors to balance temperatures
- Buyers who want a touchscreen with app control
Skip it if
- You want a thermostat under 0.62 lb
- You want a warranty longer than 3 years
It works with Sensi Room Sensors, sold separately, to balance temperatures throughout the home. It has an LCD touchscreen, Bluetooth and Wi-Fi, and control by app, touch, or voice. It works with air conditioner, boiler, furnace, and heat pump equipment, and the box holds an installation guide, mounting hardware, an owner's manual, and a warranty booklet. It carries a 3-year warranty.
Like-New Amazon Smart Thermostat
It uses Echo devices and the Smart Air Quality Monitor as temperature sensors, with Alexa control from the Alexa app.
- Room sensor support
- Works with Alexa / Google
- Phone app control
Good for
- Buyers who already use Echo devices as temperature sensors
- Buyers who want Alexa app control from anywhere
Skip it if
- You want a new, non-refurbished unit
- You want more than home, away, and sleep temperature settings
It creates comfort zones with select Echo devices or the Amazon Smart Air Quality Monitor, adjusting heating and cooling from temperature readings or presence detection. Alexa can switch between home, away, and sleep temperatures automatically, and the Alexa app guides installation. It is refurbished and certified to look and work like new, and it comes with the same limited warranty as a new device.
Honeywell Home RTH7600D 7-Day Programmable Touchscreen Thermostat
It offers 7-day programming with 4 periods per day on a backlit touchscreen, with home and away temperature settings.
- 1-year warranty stated
Good for
- Buyers who want 7-day programming with 4 periods per day
- Buyers who want a large backlit touchscreen
Skip it if
- You want a warranty longer than 1 year
- You need more than 4 periods per day
It has a large backlit touchscreen that shows current room temperature and set point temperature at the same time. It offers 7-day menu-driven programming with 4 periods per day, plus temporary and permanent hold settings. Smart Response Technology learns how long the furnace and air conditioner take to reach programmed settings. The box holds mounting hardware and a quick install guide, and it carries a 1-year warranty.
Heagstat Non-Programmable Thermostat for Home Conventional Single-Stage
It runs on hardwired power or 2 AAA batteries with no C wire needed, and gives manual Heat, Off, and Cool modes.
- Works without a C-wire
- 2-year warranty stated
Good for
- Buyers with a single-stage 1 heat, 1 cool system
- Buyers who want simple manual Heat, Off, and Cool modes
Skip it if
- You run a multi-stage or heat pump system
- You want a warranty longer than 2 years
It works with conventional single-stage 1 heat, 1 cool systems, including forced air, ventilation, and air conditioning. It has a 4.5 sq inch backlit LCD screen, a control range of 44F to 90F, and a 5-minute adjustable compressor delay protection. The box holds an installation manual, screws, and labels, and it carries a 2-year warranty.
How to choose
Check C-Wire Needs First
A C wire gives a thermostat steady power from the heating and cooling system. Some models run without one, using batteries or another power design, while others need a C wire in place before they run. The Nest Thermostat and the Heagstat H701 work without a C wire, and the Sensi Touch 2 states that a common wire is required. Check your current wiring before you pick, so the model you choose matches what is already at the wall.
Match Sensors And Controls To Your Home
Room sensors read temperature in a second room so heating and cooling can balance across rooms. The Sensi Touch 2 works with Sensi Room Sensors, sold separately, and the Amazon Smart Thermostat uses compatible Echo devices and the Smart Air Quality Monitor as temperature sensors. Voice control through Alexa or Google Assistant and control from a phone app let you change settings without walking to the wall unit. The Nest Thermostat, the Sensi Touch 2, and the Amazon Smart Thermostat all offer app control and voice control.
Compare Programming And Warranty Terms
A programmable thermostat holds a schedule across days, with set periods for heating and cooling, while a manual model holds the mode you set until you change it. The Honeywell RTH7600D offers 7-day programming with 4 periods per day, and the Heagstat H701 gives manual Heat, Off, and Cool modes with no programming. Warranty terms also differ: the Sensi Touch 2 carries a 3-year warranty, the Heagstat H701 carries a 2-year warranty, and the Nest Thermostat and the Honeywell RTH7600D each carry a 1-year warranty.
FAQ
Do I need a C wire for a smart thermostat?
It depends on the model. The Nest Thermostat and the Heagstat H701 work without a C wire, while the Sensi Touch 2 states that a common wire is required. Check your wiring and the model requirements before you buy.
Can a thermostat balance temperatures between rooms?
Some models use room sensors for that. The Sensi Touch 2 works with Sensi Room Sensors, sold separately, and the Amazon Smart Thermostat uses compatible Echo devices and the Smart Air Quality Monitor as temperature sensors.
What does ENERGY STAR certification mean on a thermostat?
It marks a thermostat that meets the ENERGY STAR program criteria for energy performance. The Nest Thermostat and the Sensi Touch 2 are ENERGY STAR certified, so buyers who value that mark can start with those two picks.
How do I control a smart thermostat from my phone?
Use the model phone app over Wi-Fi. The Nest Thermostat works with the Google Home app, the Sensi Touch 2 works with its app, and the Amazon Smart Thermostat works with the Alexa app. Each app gives remote access to temperature settings.
