Can Any ISP See Peoples Mobile Numbers Over Wi-Fi?

[justasktom]

Can any ISP see peoples mobile numbers/cell phone numbers to thier smart phone devices when they connect to them over wi-fi?

Like when people want to save data usage by switching thier smart phones' cellular service to the wi-fi service in thier homes or the wi-fi at a friends place etc.

Please give an explanation as to why or why not. Thank you guys for sharing your knowledge.

 

[hang-the-9]

If you are using the data plan, they will see your IP not your phone number. If you are using WiFi calling, then your number is sent along with that data to make the call.