Smart Thermostat Guide

Independent WiFi thermostat reviews since 2014

Our Picks: 2021’s Best Smart Thermostats

Our top picks for 2021 offer robust feature sets, easy installation, compatibility with a wide variety of HVAC systems, and integration with home automation assistants such as Amazon’s Alexa and Google Home.

Ecobee SmartThermostat – Alexa-integrated thermostat offers convenience and the smartest room sensors on the market today.

Honeywell T9 – this competitively priced model from an established name in thermostats comes with a room sensor and C-wire kit.

Emerson Sensi – our long-time favorite skips the sensors and expensive screen in favor of a streamlined experience at a surprisingly low price.

Nest Learning Thermostat – the stylish original is still a solid (and popular) choice due to its ease of use, integration with the larger Nest ecosystem, and variety of colorful finishes.

Automating the temperature of your home has never been easier. Today’s smart thermostats are easy to set up and include smart features designed to help you save money on your monthly energy bills without sacrificing comfort. Nearly all of today’s WiFi-enabled thermostats can be managed via Google Home or Apple HomeKit, making it easy to centralize control of your smart home in one app.

Why upgrade to a smart thermostat?


No need to get up (or even be home) – a smart thermostat lets you adjust the temperature from your smartphone or by speaking to a smart assistant, such as Amazon’s Alexa or Google Assistant.


Smart thermostats make it easy to set a heating and cooling schedule that adapts to the current weather, the changing seasons, and your own schedule to save you money.

Gone are the days of trying to program a schedule on a tiny LCD screen using only a couple buttons. Today’s modern smart thermostats can be scheduled via their smartphone app or web portal, making it easy to develop detailed schedules.


Today’s smart thermostats all have their own ways of giving users a high-level overview of their recent energy usage. Nest rewards users with a little “leaf” icon for choosing “energy efficient” settings and shows usage over the past several days. Ecobee generates an emailed report after each calendar month. None of these reports are exceptionally detailed, but if you’re new to trying to optimize your energy usage, they can be a nudge in the right direction.

Is my home compatible with a smart thermostat?

Line voltage, low voltage – what’s the difference? The vast majority of what we call smart thermostats are only compatible with so-called “low voltage” HVAC systems.

Here’s our visual guide to wires, voltage, and more to help you identify your home’s heating and cooling setup.


C-wire questions, answered

WiFi is power-hungry and cannot run off a battery or intermittent current. You’ll need continuous power to keep the thermostat connected. Most smart thermostats designed for a 24v HVAC system require a common wire (also called a c wire) or some kind of workaround, which vary by manufacturer.


Best Value Smart Thermostats for 2021

Ecobee3 Lite brings everything we love about ecobee thermostats at a budget-friendly price: it’s easy to use, compatible with a wide variety of HVAC setups, and can be expanded with room temperature sensors (sold seprately).

Nest Thermostat E might be budget-priced, but it’s still got the the learning algorithm that made Nest famous and a beautiful display.

Emerson Sensi is easy to use and schedule and works without a C-wire. See why this no-nonsense thermostat is a reader favorite. 

About us

We are a small team of tech nerds across North America who have been reviewing smart thermostats such as the Nest and the Ecobee since 2014. We are independent (that means we don’t accept any freebies) and run this site as a hobby out of love for home automation technologies.

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