65 ILCS 5/3.1-25-10
Any village board of a village of under 5,000 population incorporated under this Code may by resolution provide for a referendum on the question of whether the board of trustees shall be comprised of 4 members rather than 6 members. The referendum shall be held in accordance with the general election law. If a majority of those voting on the question vote in favor of reducing the number of trustees from 6 to 4, the number of trustees shall be reduced to 4. In order to provide for the transition from 6 member boards to 4 member boards, 2 trustees shall be elected at the general municipal election in each odd numbered year after the adoption of the referendum when trustees are elected for 4 year terms and at the general municipal election in each year after the adoption of the referendum when trustees are elected for 2 year terms. Any village that changes from a 6 member board to a 4 member board may thereafter return to a 6 member board by the same procedure.
65 ILCS 5/3.1-25-10