Main office
118 North Clark Street
Third Floor, Room #320
Chicago, IL 60602
Phone Number
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The mission of the Cook County Assessor’s Office is to serve the public both professionally and responsibly by establishing uniform and accurate property assessments. Assessed values are set on real estate as a basis for levying taxes and determining the distribution of property tax levies among taxpayers.

Mandates and Key Activities

  • As part of the Valuation and Appeal Process, the County Assessor follows and enforces state and county laws and ordinances: Classification of Property 35 ILCS 200/9-150
    • Classification Ordinance Cook County Code of Ordinances, Chap. 74, Art. II, Div. 1, Sec.74-31 et seq. and Div. 2, Sec.74-60 et seq.
    • Assessment by Districts 35 ILCS 200/9-220 Omitted Property 35 ILCS 200/9-260, 9-270 Publication of Assessments 35 ILCS 200/12-20
    • Assessment Notices of Increases 35 ILCS 200/12-55 Certificates of Correction 35 ILCS 200/14-10 Certificates of Error 35 ILCS 200/14-15
    • Revision of Assessments 35 ILCS 200/14-35
    • Valuation of Particular Types of Property 35 ILCS 200/10-5 thru 10-620
  • The County Assessor provides taxpayer assistance via the review, processing, and administration of Exemptions through the following ordinances and laws: Disabled Veterans 35 ILCS 200/15-165
    • Returning Veterans Homestead 35 ILCS 200/15-167 Disabled Persons Homestead 35 ILCS 200/15-168
    • Disabled Veterans Standard Homestead 35 ILCS 200/15-169 Senior Citizens Homestead 35 ILCS 200/15-170
    • Senior Citizens Assessment Freeze 35 ILCS 200/15-172 General Homestead 35 ILCS 200/15-175
    • Alternate General Homestead 35 ILCS 200/15-176 Long-time Occupant Homestead 35 ILCS 200/15-177 (This role includes significant outreach, communications, and religious exemption programs as well as responding to thousands of taxpayer inquiries and certificates of error.)
  • The County Assessor enforces the Erroneous Exemptions legislation (35 ILCS 200/9-275), designed to target property owners who erroneously received property tax exemptions.