Once you've successfully installed your new ecobee, you can register on your ecobee mobile app or on the web portal. To do so, go to Menu > Registration on you ecobee thermostat to obtain your registration code. Then, click Register on your home screen to proceed.
Once you have obtained your four digit registration code from your thermostat, it can be entered in the mobile app after selecting "Register your thermostat" on the home screen, or on the web portal at www.ecobee.com/register.
Note: Your ecobee thermostat must be installed and online in order to obtain a registration code.