About
The Assessor's Office
The Assessor's Office is responsible for setting fair and accurate values for 1.8 million parcels of Cook County property. The value of these properties is not determined on an individual basis, but rather by a mass appraisal system. The mass appraisal system is a way to put fairness into the entire assessment process.
Our public service responsibilities, however, are not limited to setting property values. In addition to working with other government agencies to stimulate economic development, job creation and the construction of affordable housing, we also seek to help county residents better understand the assessment process and take advantage of money-saving exemptions the office provides.
The Assessor's Office has also taken the lead on developing both short-term property tax relief proposals as well as working toward the overall restructuring of the tax system to make it more equitable for all taxpayers.
The Role of the Cook County Assessor
The Cook County Assessor is an elected government official who is responsible for establishing fair and accurate property assessments. Valuation of the county’s 1.8 million parcels of property is conducted for ad valorem tax purposes. Ad valorem means according to real estate value and refers to the amount of tax a property is required to pay based on its value.
To administer this task, the Assessor reassesses one-third of the properties located in the county each year. The Assessor alternates assessments among the northern suburbs, the southern suburbs and the City of Chicago. For example, a property reassessed in 2012 will be reassessed next in the year 2015.
The Assessor's Role In the Tax Cycle
The Cook County Assessor places a value on close to 1.8 million parcels in Cook County.
Triennial Reassessments
Reassessment of property in Cook County is done within a triennial cycle, meaning it occurs every three years. The Cook County Assessor's Office alternates reassessments between the north and west suburbs, the south and west suburbs and the City of Chicago.
Triennial Reassessment Cycle & Map
Reassessment Years 2012 and 2015 |
|
| Townships |
| Hyde Park |
Jefferson |
Lake |
| Lakeview |
North |
Rogers Park |
| South |
West |
|
|
Reassessment Years 2013 and 2016 |
|
| Townships |
| Barrington |
Elk Grove |
Evanston |
| Hanover |
Leyden |
Maine |
| NewTrier |
Niles |
Northfield |
| Norwood Park |
Palatine |
Schaumburg |
| Wheeling |
|
|
|
Reassessment Years 2014 and 2017 |
|
| Townships |
| Berwyn |
Lyons |
River Forest |
| Bloom |
Oak Park |
Riverside |
| Bremen |
Orland |
Stickney |
| Calumet |
Palos |
Thornton |
| Cicero |
Proviso |
Worth |
| Lemont |
Rich |
|
|
Valuation through Multiple Regression
To determine the property value of a single family home, the Assessor's Office uses a technique called multiple regression. This technique creates a type of sales comparison average, a mathematical relationship between the value of your house and those of your neighbors.
The key concern in property assessment is uniformity. The rule of uniformity requires that property be valued with property of like kind. The sales comparison average ensures that similar properties are therefore assessed similarly.
Mapping the Townships
An integral part of the assessment process is the collection of data regarding economic and neighborhood trends. One use of this data is to define neighborhoods which have similar housing types and sale prices.
These 'assessment neighborhoods' are mapped and assigned neighborhood codes, a necessary component of the multiple regression process.
In suburban townships or Chicago neighborhoods which will undergo triennial reassessments, the Assessor's Office staff meets with local elected officials, community leaders, real estate professionals and other citizens knowledgeable about real estate in the area. This helps to verify or correct assessment neighborhood boundaries before they are finalized.
The Appeals Process
With nearly 1.8 million parcels of property in Cook County, mistakes may occur during the assessment process. The Assessor’s Office encourages taxpayers to review their proposed assessments and file appeals if necessary.
Friendly, informative service is the aim of the Assessor's Taxpayer Services Department. If taxpayers are not satisfied with the results of their appeals, they are encouraged to contact the Assessor's Taxpayer Advocate Department, which will conduct an individualized re-review of an appeal.
Tax Savings through Exemptions
Property owners should be aware that there is tax relief available through property tax exemptions.
