At some point you may want to enable your mobile phone to make your outgoing calls come from a "private" number that won't be displayed on the recipient's caller ID system. Though making private calls from a landline phone is a fairly well-known process, many people are unaware of the process for hiding numbers for mobile calls. Whether you want all your calls to be private or just one, knowing how to set your mobile phone up in order to hide your number can be a very useful technique to have. The process for making your number private for all calls varies from phone to phone, but many models follow a similar process.
Navigate to the menu on your mobile phone.
Click the "Settings" option and look for an option for "Call Settings."
Click the "Call Settings" option and look for an option for "All Calls" or "General Call Settings."
Select the "Show My Number" option and then select "Hide."
Navigate to the menu on your iPhone.
Click the "Settings" tab and look for an option for "Phone" from the "Settings" menu and select it.
Look for the option "Show My Caller ID" and then choose "Off."
Click "Menu" on the main screen and then scroll and select "Settings."
Scroll down and select "Call" from the settings menu.
Scroll down and select "Send my caller id" from the call menu and then select "No."
To make your number private for a single call from most mobile phones in North America, dial 67 in front of the telephone number you are trying to call. For example, if you were trying to dial 1-303-333-3456, you would instead dial 671-303-333-3456. To make your number private for a single call from most iPhones, dial #31#. When changing call settings, it may be necessary to power the phone off and back on for the changes to take effect.