55 ILCS 5/6-1006
The county treasurer shall keep a separate account with each fund to show at all times the cash balance thereof, the amount received for the credit of such fund, and the amount of the payments made therefrom. Except as otherwise provided, the county auditor in each county under township organization containing over 75,000 inhabitants and the county clerk in each other county shall keep a similar account with each fund, and in addition shall maintain an account with each appropriation of each fund to show: (a) the amount appropriated, (b) the date and amount of each transfer from or to such appropriation and the appropriations to which or from which transfers were made, (c) the amount paid out under the appropriation, (d) the amount of outstanding obligations incurred under the appropriation, (e) the amount of the encumbered balance of the appropriations, and (f) the amount of the free balance of the appropriation. With respect to a County Bridge Fund, a Matching Tax Fund, and a Motor Fuel Tax Fund, the county auditor in a county under township organization containing over 75,000 inhabitants and the county clerk in each other county may, but is not required to, keep an account with each appropriation of each fund as referenced above.
55 ILCS 5/6-1006