How To Turn Off Voicemail On Iphone. Enter 404 and tap Call to disable your voicemail service. The only way to fully disable your voicemail is to call your mobile provider to request the feature be turned off.
Type 004 without quotes and press Call This should deactivate your voice-mail service.
Make sure you are in the keypad section. Disable the voice mail. At this point type the voice mailbox number on the space that will be provided and then you can now exit after saving the settings. Heres how to do that.