How To Activate Comcast Xfinity Services Online Via www.comcast.com/activate
- Visit www.comcast.com/activate.
- Then, Sign in if you have a User ID.
- Next, type in your account number. This can be found on your Activation Card or receipt in your Self Install Kit, or on your bill.
- Enter your 10-digit telephone number that Comcast has on file for your account.
- Finally, click “Next” to start activating your services.