35 ILCS 200/18-155
2021 Illinois Compiled Statutes|Chapter 35 - REVENUE|35 ILCS 200/ - Property Tax Code.|Title 6 - Levy and Extension

Sec. 18-155. Apportionment of taxes for district in two or more counties.   The burden of taxation of property in taxing districts that lie in more than  one county shall be fairly apportioned as provided in Article IX, Section 7, of  the Constitution of 1970.The Department may, and on written request made before July 1 to the  Department shall, proceed to apportion the tax burden.  The request may be made  only by an assessor, chief county assessment officer, Board of Review, Board of  Appeals, overlapping taxing district or 25 or more interested taxpayers.  The  request shall specify one or more taxing districts in the county which lie in  one or more other specified counties, and also specify the civil townships, if  any, in which the overlapping taxing districts lie.  When the Department has  received a written request for equalization for overlapping tax districts as  provided in this Section, the Department shall promptly notify the county clerk  and county treasurer of each county affected by that request that tax bills  with respect to property in the parts of the county which are affected by the  request may not be prepared or mailed until the Department certifies the  apportionment among counties of the taxing districts' levies, except as  provided in subsection (c) of this Section.  To apportion, the Department  shall:(a) On or before December 31 of that year cause an assessment ratio  study to be made in each township in which each of the named overlapping  taxing districts lies, using equalized assessed values as certified by the  county clerk, and an analysis of property transfers prior to January 1 of  that year.  The property transfers shall be in an amount deemed reasonable and  proper by the Department.  The Department may conduct hearings, at which the  evidence shall be limited to the written presentation of assessment ratio study  data.(b) Request from the County Clerk in each County in which the overlapping  taxing districts lie, certification of the portion of the assessed value of the  prior year for each overlapping taxing  district's portion of each township.  Beginning with the 1999 taxable year, for  those counties that classify property by  county ordinance pursuant to subsection (b) of Section 4 of Article IX of the  Illinois Constitution, the certification shall be listed by property class as  provided in the classification ordinance.  The clerk  shall return the certification within 30 days of receipt of the request.(c) Use the township assessment ratio studies to apportion the amount to be  raised by taxation upon property within the district so that each county in  which the district lies bears that burden of taxation as though all parts of  the overlapping taxing district had been assessed at the same proportion of  actual value.  The Department shall certify to each County Clerk, by March 15,  the percent of burden.  Except as provided below, the County Clerk shall apply  the percentage to the extension as provided in Section 18-45 to determine the  amount of tax to be raised in the county.If the Department does not certify the percent of burden in the time  prescribed, the county clerk shall use the most recent prior certification to  determine the amount of tax to be raised in the county.If the use of a prior certified percentage results in over or under extension  for the overlapping taxing district in the county using same, the county clerk  shall make appropriate adjustments in the subsequent year, except as provided by Section 18-156.  Any adjustments  necessitated by the procedure authorized by this Section shall be made by  increasing or decreasing the tax extension by fund for each taxing district  where a prior certified percentage was used. No tax rate limit shall render any  part of a tax levy illegally excessive which has been apportioned as herein  provided.  The percentages certified by the Department shall remain until  changed by reason of another assessment ratio study made under this Section.To determine whether an overlapping district has met any qualifying rate  prescribed by law for eligibility for State aid, the tax rate of the district  shall be considered to be that rate which would have produced the same amount  of revenue had the taxes of the district been extended at a uniform rate  throughout the district, even if by application of this Section the actual rate  of extension in a portion of the district is less than the qualifying rate.  (Source: P.A. 99-335, eff. 8-10-15.)