It may be necessary to hide your number when you are calling someone. Perhaps you were testing to see whether a phone number works, but you did not want to show your number. You may be using your cell phone for business and may not want a client to have your cell-phone number. Whatever your reason, you can hide the number by following a simple process.
Contact your cell-phone service provider and ask them to block your cell-phone number if you want the number blocked each time you make a call. You can disable this option at any time by calling again and having them remove the block.
Block the number temporarily by dialing *67. Dial the number after hearing the dial tone. Your number will be blocked for that call only.
Call your Caller ID-enabled home phone or a friend to test that the call is blocked. The number should come up as blocked, private or unavailable.