I have tried to insure that my calls on my notes are made over wireless connections only. I have tried marking all options I can find. However I am in Costa Rica and called a costa Rican number and the call went through, so concerned that I did not stop the potential for be billed for these calls.
If you are wanting to make data calls and have a data app capable of such, you need to turn on airplane mode then turn on WiFi. Any call made with a Note 4 will be wireless.