Cook County property owners still missing out on appeals

map of cook county illinois with color highlighting of regions according to the percentage of properties that appealed their assessed value.
Wed, Aug 19, 2020
  • Only 20% of property values were contested by owners in 2019
  • Property owners who appealed saved an average of $310

The Cook County Assessor’s Office (“CCAO”) has released numbers on all residential property tax appeals filed for 2019 and the data is clear: only a fraction of property owners appeal. Only 20% or 1/5 of property assessments were appealed in 2019 and as shown in the above map, appeals were concentrated in the North Suburbs.

Presumably, a higher percentage of North Suburbs property owners submitted appeals because those properties were reassessed in 2019 and the CCAO mailed letters to those owners notifying them that their property taxes might change significantly as a result.

It seems that most residents still don’t know that they can appeal every year, and not just when their property is reassessed. Property values can change on a monthly basis, much less yearly, and therefore it is likely that properties are inaccurately valued by the County. By law, assessed values cannot be increased because of an appeal, so Cook County property owners are missing out on potential savings.

Savings Breakdown

Around 30%1 of appeals succeeded in lowering assessed value. Of those that were successful, the breakdown in taxes saved by the property owners was:

Taxes Saved Number of Properties Percent
Up To $250 20,218 21%
$250-$500 25,649 27%
$500-$1000 23,897 25%
More than $1000 26,088 27%

50% of property owners who appealed saved more than $500.


The CCAO generally reassesses Cook County properties once every 3 years. In 2020, as a response to the ongoing COVID-19 pandemic, the CCAO is reassessing all properties:

Year County Triad Reassessed
2015 City
2016 North
2017 South
2018 City
2019 North
2020 ALL

Help Filing Appeals

NulliTax can appeal your property’s assessed value for you. We provide a search tool on our homepage to find your property and estimate savings.

  1. 29.68% ↩︎