35 ILCS 200/11-110
The equalized assessed value of the operating property of every railroad company subject to assessment, when determined as prescribed in Section 11-80, shall be listed and taxed in the several taxing districts in the proportion that the length of all the track owned or used in such taxing district bears to the whole length of all the track owned or used in this state, except the value of all buildings of an original cost exceeding $1,000, which are considered to have a situs in the taxing district in which they are located. Where any railroad company operates in this State, in whole or in part over the tracks of another company, under any trackage right agreement, the value of the trackage rights, including the other taxable operating property (except buildings of an original cost exceeding $1,000) used or connected therewith, shall be taxed in each taxing district in the proportion that the length of all the track so used under the agreement, in the taxing district bears to the whole length of all the track so used in this state. Where a railroad company holds taxable operating property in a taxing district, and owns or uses no tracks, or trackage rights in that district, the property shall be taxed in the taxing district.
The Department shall distribute the equalized assessed value of the taxable property of every railroad company (other than non-carrier real estate), when determined as prescribed in Section 11-80, to the respective taxing districts entitled to it and shall certify the same to the county clerks of the respective counties, who shall extend taxes against those values the same as against other property in the taxing districts.
35 ILCS 200/11-110