People sometimes feel the necessity to make or return phone calls privately. Any individual can prevent his phone number from being revealed for a single call simply by dialing *67 before dialing the recipient number. This is a cost effective alternative to placing a permanent "block" on your phone number because most telephone companies charge a monthly rate.
Pick up the telephone. Listen for the dial tone.
Dial 67, followed by the nine digit number. Dial all together and avoid waiting for a pause between the 67 and dialing. For example, to call 1234567890, dial *671234567890.
Click the "Send" button on your phone. The call will go through, appearing as "private number" on the recipient's caller ID.