Call Forwarding Busy Line
Call Forwarding Busy Line lets you forward your calls to a pre-programmed number such as an answering service whenever your phone line is busy. You can use this service with regular call forwarding, but when regular call forwarding is activated, call forwarding busy line will be deactivated.
The pre-programmed number you designate is normally pre-set and cannot be changed at will.
Some telephone companies, especially VoIP providers will allow you to modify the forwarding number through a web portal or by dialing a *xx code.
Call Forwarding instructions by provider :
AT&T – call forwarding instructions
Qwest - call forwarding instructions
Verizon – call forwarding instructions
Verizon Wireless - call forwarding instructions
Vonage - Call Forwarding Instructions
Metro PCS - call forwarding instructions
Skype - call forwarding instructions