It isn't always convenient to let someone know that you're calling from a cell phone, or to show someone that it's actually you calling. For situations like this, there are ways to block your phone number from being sent on caller ID. Depending on your phone, you may have the option to do it permanently from your "Call Settings" menu, but not all phones have this ability.
Power on your cell phone and go to the menu.
Select "Settings" and then "Call Settings." Scroll down until you see the "Send own number" choice, or something similar. Select "NO". If your phone has this ability, then you have just blocked your number from being seen. If you want to undo it, simply switch back to, "YES" or "SET BY NETWORK."
Enter the command 67 before you dial.. If your phone doesn't have the ability to self-block your number, this will do it. However, this will have to be done before each call. It's a temporary solution. If you want to use this option, the number you dial should look similar to, "675555555" where (5555555) is the number you wish to dial.
Call Sprint Customer Service by dialing *2 from your cellphone. Or, alternatively, call 888-211-4727 if you're not on the Sprint Network at the time. Tell the customer service rep that you wish to block your outgoing caller ID information. The rep will put a note in the computer, and your number will be blocked. If you wish to undo that, simply call them back.