Your best bet is to call Charter customer support and ask, but this product is meant to be plugged directly into a modem, not a wireless router/modem from a cable company. This will allow you to buy a cheap DOCCIS 3.0 modem and stop paying Charter $5-10 a month for their box. Plug the Google wifi into the modem, download the app on your phone, and you'll be up and running within 5 minutes.