Activate XFINITY Modems – 7 Easy Steps

Activate XFINITY Modems Setup Diagram

Easily activate XFINITY modems by following these easy steps. Self-Activation is available online. There is no need to call Comcast. If you need a new XFINITY modem, you can find one for your needs here. See all XFINITY Cable Modems. 

Locate Comcast Account Number

Find your Comcast account number and phone number associated with your account. This is located on your bill. You may need this information. 

Unplug and Remove Old Equipment and Hook Up New Modem

Disconnect any old equipment. Connect a new modem or gateway to the coax, wall outlet, and PC only. If you have a router leave it out of the configuration for now. After the modem itself is activated, the router can be connected. Coax connections should be finger tight to avoid signal loss.


Get The Green Light

Wait up to 10 minutes for the online light to be green on the modem. 

Enter XFINITY Set-Up Page

Open a web browser from a computer. To activate XIFNITY modems, go to the Comcast web page www.xfinity.com/activate  only if it does not automatically open.

Follow Screen Prompts To Activate XFINITY Modems

Follow the onscreen prompts to begin activation. You will need your account info if you have not yet setup a username & password. 

Modem May Now Reboot

The rest of the installation is pretty straight forward, following the on-screen instructions. After the modem has been set up, it may reboot. Once this occurs and the modem is back up and running, you can then connect a router. If you require further assistance, you can contact XFINITY support. Additionally, if you purchased your new modem from Amazon, it may have come with 90-days of free tech support. View your ordered items and select contact support if available. You may also call the manufacturer of the modem for support as well. 

Return Old Equipment To Comcast

Sign in to your XFINITY account and select the Equipment Return page. Here, you can initiate the return process. Alternatively, you can simply just go to any UPS Store, XFINITY Customer Center, or XFINITY store. Make sure the serial numbers on your equipment match that in your Comcast account. Another option – if you kept the return label from when you received your self-install kit, you can use that to return your equipment. Either way, you can track your return status online here.


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