Xfinity.com/authorize | xfinity.com/activate | Xfinity on Roku | how to activate xfinity internet xfinity.com/activate is the activation site for the Xfinity channel. After getting the channel activation code, you will have to provide it in this link. Check it before starting with the activation process, and this can lead to channel activation errors. Click Activate option, and then the channel gets added to the Roku channel list. Call us @ +1-844-893-6700