The league consisted of the 18 first-class county teams divided into two divisions of nine teams each with fixtures played between May and August.
The final took place at Edgbaston Cricket Ground in Birmingham on 20 August 2016.
Teams were initially split into 2 divisions (North and South), each containing 9 teams, for the group stage of the competition.
During the group stage (from May to July) each club plays 6 of the other teams in the same division twice, once at their home stadium and once at that of their opponents.
Teams are ranked by total points, then net run rate.