65 ILCS 5/8-2-1

Pursuant to the provisions of Sections 8-2-1 through 8-2-8, the corporate authorities in municipalities with a population of 500,000 or more, shall pass an ordinance within the last 60 days of each fiscal year, to be termed the annual appropriation ordinance. In this ordinance the corporate authorities, subject to the limitations contained in Sections 8-2-1 through 8-2-8, may appropriate such sums of money as are deemed necessary to defray all necessary expenses and liabilities of the municipality to be paid or incurred during the next fiscal year.