A customer can turn off call forwarding by pressing a few keys on the mobile device in a specific order. Each service provider has its own code for turning call forwarding on and off.
To turn off call forwarding on a Verizon device, dial *73 and listen for the message or tone indicating the feature is off. On an AT&T phone, dial #21# and then press the Call button. The provider sends a text message when the feature is deactivated. If using a Sprint device, use the code *720 and press the Send button. Verizon also offers the ability to turn off call forwarding online. A customer can log into his or her account and follow directions on the Call Forwarding page.