How to set up conditional call forwarding on your AT&T cell phone: Follow these simple steps!
Step 1: Using the keypad on your cell phone, dial *004* (do not press call yet.)
Step 2: After dialing *004*, enter the 10 digit telephone number you would like your calls forwarded to.
Step 3: Then press *11#.
Step 4:Press call and listen/look for a success message from AT&T.
To turn off conditional call forwarding from your AT&T cell phone, simply punch in #004# and press call. Listen for a successful message stating call forwarding has been deactivated