Is a Reverse Cell Phone Directory offered by T-Mobile?
For a secure method to perform a reverse phone search, consider using a people search service such as National Cellular Directory.

Change Your Cell Phone Provider and Transfer Your Number - T-Mobile
What is the process to move my phone number to T-Mobile?

Get in Touch | T-Mobile
Calls to this number from landline phones and non-T-Mobile devices will result in international long distance charges plus any additional fees that might apply...