Best Smart Thermostats that Don't Require a C Wire Android Central 2020

The C wire ("common" wire) is the wire that provides continuous power to your thermostat. Older thermostats didn't really need it because they were simple on/off affairs, but smart thermostats, what with their displays and constant connection to Wi-Fi, need continuous power. That being said, if you don't already have a C wire in your system, you can get around having to install one with these smart thermostats.

Simple and straightforward: Nest Thermostat E

Staff favorite

This stripped-down version of Nest's Learning Thermostat is a great option for folks who don't want to spend too much and prefer things to be minimalist. The display simply shows the temperature setting, and it's frosted to blend into your decor. The Thermostat E features a built-in rechargeable lithium-ion battery.

$170 at Best Buy

The O.G.: Nest Learning Thermostat (third generation)

Nest's Learning Thermostat was first on the scene, and its third generation has improved upon that original formula with a powerful feature set, gorgeous display, and multiple color options. This one doesn't need a C wire, though I have read about some power cycling issues that may or not be an issue for you. It may be worth the risk for the excellent learning capabilities and Alexa/Google Assistant integration.

$249 at Amazon

The best, period: ecobee SmartThermostat (5th generation)

ecobee's latest iteration in its smart thermostat line-up builds upon everything that makes its predecessors great (up to 32 room sensors, great display, plays nice with all the smart assistants) by adding built-in Alexa voice control. Like its ecobee brethren, the 5th-gen model doesn't need a C wire, but it does come with a power extension kit that is required if you don't already have a C wire.

$249 at Amazon

Second best: ecobee4

If you want a smart thermostat that works with all the assistants, is full-featured, and expandable with multi-room sensors, then ecobee is what you want. The ecobee4 is a little less expensive than its new counterpart, and it comes with the adapter kit that circumvents the need to install a C wire; there's still some electrical installation required, but nothing as cumbersome as running wire through your house.

190 at Amazon

Best brand, lowest cost: ecobee3 lite

The ecobee 3 lite is missing a few convenience features that the 4 has, like a built-in occupancy sensor and built-in voice control. However, it's an excellent budget option, and you can still fully control your home's heating and cooling from anywhere in the world through the app, or in your home with smart assistant devices. The ecobee3 lite also comes with the power extension kit that lets you bypass the need for a C wire.

$169 at Amazon

Budget pick: Emerson Sensi Wi-Fi Smart Thermostat

If you don't mind a bit of a dated look and lack of 24/7 light-up display, then Emerson's Sensi smart thermostat is your best budget pick. It only requires a C wire for heat- and cool-only systems (or heat pumps), and it still has full Wi-Fi connectivity, with a straightforward app, easy program controls, and minimal setup required.

$99 at Amazon

No C wire? No problem!

The need for a C wire can certainly stunt your smart thermostat search, but if you'd prefer not to have to install one, then the Nest Thermostat E is your best option — and it's rather affordable. It's also a simple, no-frills thermostat with Google Assistant and Alexa capabilities, and that frosted display is slick and unobtrusive.

If you do, however, have a little electrical know-how, the ecobee SmartThermostat is the best smart thermostat money can buy, and the power extension kit makes life much easier. From its gorgeous display to its multiroom sensor integration, built-in Alexa, and solid speaker (that will even let you play your Spotify jams!), ecobee's offering is truly the king of smart thermostats — and its price reflects it.

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