The Mountain West Conference and Conference USA say they are combining their football programs to form a 22-team league.
The new conference will spread across five time zones from North Carolina to Hawaii.
Mountain West commissioner Craig Thompson says the leagues made the move to join instead of waiting for teams to be poached or otherwise affected by conference realignment.
The conferences did not say when the merger would take place, nor what the new association would be called.
The University of Alabama at Birmingham (UAB) is the only member of the conference within the state of Alabama.