What smart thermostats work with Alexa? Having a smart thermostat is great, and controlling from your phone is a huge step up from manual thermostats but having Alexa voice control of your smart thermostat is a true luxury. The nest thermostat works with alexa voice commands and adds additional functionality to your smart home system. The ecobee generation 4 smart thermostat works with Alexa and actually has Amazon Alexa built in. Inside the Ecobee 4 smart thermostat there is a small speaker and microphone to allow for full Amazon Alexa functionality inside of the Ecobee 4 thermostat. There are several other smart thermostats that work with alexa but the most popular the smart thermostats that work with alexa are nest and ecobee.