Dial *67 before the phone number on most North American carriers
Use your phone’s Caller ID settings to turn off outgoing caller ID
On iPhone, go to Settings > Phone > Show My Caller ID > turn off
On Android, open the Phone app > Settings > Calling accounts or Supplementary services > Caller ID > hide number
Ask your carrier to block your caller ID for all outgoing calls
Use a VoIP app or service that allows caller ID blocking
Enter the carrier-specific caller ID blocking code if your country uses a different prefix
Check that the recipient’s phone and carrier do not override caller ID blocking
Use a separate business line or secondary number if you need privacy