Amazon Smart Thermostat with C-Wire Adapter

Why it's worth it

This is the least complicated way into voice-controlled heating if your house already runs on Alexa. It drops into existing routines with no setup, and the bundled C-Wire Power Adapter handles older systems that most competitors make you solve yourself.

The bundled C-Wire Power Adapter is the reason to buy this specific listing. Older houses frequently lack a common wire, and that single missing wire kills more smart thermostat purchases than any other factor. Most competitors sell the adapter separately or leave you to source one. Here it's in the box, which turns a potential returns headache into a slightly longer install.

Alexa integration is as deep as it gets, because Amazon built both ends. Say good night and the thermostat drops with the lights and the locks, no custom configuration required. If you've already got Echo devices scattered around the house, this slots in without you thinking about it.

From our review of 6 smart thermostats with voice control, by David Sinclair, Managing Editor

What we like

• +The bundled C-Wire Power Adapter is the reason to buy this specific listing
• +Alexa integration is as deep as it gets, because Amazon built both ends
• +Be clear-eyed about what you're getting
• +Owners coming from Nest describe it as a surprisingly capable substitute for the basics

What to know

• –The display and materials are plain
• –Installation isn't always trivial despite the adapter
• –It's Alexa or nothing in practice