The Assessor’s Office reassesses approximately one-third of the property in Cook County each year. We began in 2020 with the scheduled reassessment of properties in the south and west suburbs, and of specific properties in the north suburbs and Chicago with divisions, permits, or other special applications that indicate changes to the properties. After we began our work, however, the COVID-19 pandemic led to substantial economic, social, and market effects.
An explanation of the Office’s initial analysis of these effects was released on May 28, 2020, in the CCAO’s report “Cook County Assessor’s COVID-19 Adjustments to Property Assessments in the South and West Suburbs." This initial report contains a summary of the methodologies used by the CCAO to produce COVID-19 adjustments to residential and commercial property values for townships in the south and west suburbs, which were scheduled for reassessment in 2020.
The report provided below describes the Assessor's application of COVID-19 adjustments to properties located in the northern suburbs and the City of Chicago in 2020.
Overall, the same analysis and approach used to adjust residential property assessments in the south and west suburbs were used in the north suburbs and the City of Chicago. A map of these adjustments can be found below.
Details on the approach to value adjustments to commercial properties throughout the county can be found in these reports.
Map of COVID-19 Residential Adjustments
COVID-19 Adjustments to Property Reassessments
Watch this video of the Assessor's Data Team on Chi-Hacknight explaining how the COVID-19 adjustments were applied and how values were calculated. The code can be accessed by clicking the button below.