Hi, deloria! Thank you for posting your question! If you have a Voice Unlimited Plan, you can call Canada, China, India, Mexico, South Korea, Hong Kong, Singapore, and Puerto Rico at no additional cost. If you are not sure what plan you have - it's listed on your billing statement that can be viewed in My Account app or webpage. You can find more information here: https://www.xfinity.com/international-voice?pc=1.
Feel free to reach out to me and I can check what plan you have as well. Please send me a private message and include your full name, the account holder's name as it's listed on the billing statement. Click on my name ComcastElla, then click Send a message.