65 ILCS 5/7-6-6
After the acting corporate authorities of the dissolved municipality (1) have paid all of the debts and obligations of the municipality, (2) have closed up all of the municipal business, and (3) the surplus money, if any, has been paid to the school treasurer for the proper township or school unit, then the acting corporate authorities shall file with the county clerk of the county in which the dissolved municipality was situated, a statement under oath, showing all of the closing up transactions. When this statement is filed, the duty to close up the municipal business is terminated, and all officers of the municipality, whether the terms for which they were elected have expired or not, shall thereupon cease to have any power or authority.
65 ILCS 5/7-6-6