How to configure default phone call app on Mac Skype for Business has been my Mac's default phone call app ever since I installed it. Is there a way to switch to FaceTime—or better yet, handoff to iPhone?

When I place calls from my iPhone, I can switch the audio to my Mac.
Open FaceTime on your Mac, select FaceTime > Preferences, select Settings, then change Default for calls to FaceTime.


via https://discussions.apple.com/thread/7715107