Assessment Calendar and Deadlines

Last updated: 8/17/2022

As townships are certified by the Board of Review for the 2021 assessment calendar below, they will be noted in the Pass column. Only rows with the words BOR Final are currently available on the CCAO website and data subscription service. 

A plus symbol (+) in that column indicates the data is certified but is not yet available on the CCAO website or the data subscription service due to the need to transfer the data from the mainframe used by the Board into the new, modern assessment system of record used by the CCAO. Updates will be made as new township data is available.

2022 Assessment Calendar: North Suburbs

Dates will be published as Reassessment Notices are mailed, when townships are open for appeals, and as values are certified for north suburban townships listed below.

Our phone lines remain open to the public during normal business hours and assistance is available via our website and social media channels.

Notices are mailed out and appeals open after 6 pm on the date listed for each township. Note that values may take an additional business day to update online from the mail date.

* Once assessment rolls are certified, the information is made available online and to all offices of the Cook County property tax system. By law, the assessment roll must also be published in a print newspaper. The "published" date refers to when the information will be available in the newspaper.

2022 Assessment Calendar: South/West Suburbs and City of Chicago

In the City of Chicago and South / West Suburban townships, individual properties will only be reassessed only if there is a change due to division work, permit applications, or other special applications.

Note that values may take an additional business day to update online from the mail date.

* Once assessment rolls are certified, the information is made available online and to all offices of the Cook County property tax system. By law, the assessment roll must also be published in a print newspaper. The "published" date refers to when the information will be available in the newspaper.

2021 Assessment Calendar: City of Chicago

Last updated: 7/10/2022

+ These townships are certified by the Board of Review but the data is not yet available on the CCAO website due to the need to transfer the data from the mainframe used by the Board into the new, modern assessment system of record used by the CCAO.

The 2021 assessment and appeal schedule coincides with the implementation of iasWorld, a new integrated property tax system. This upgrade moves us from an aging mainframe system onto a state-of-the-art platform that allows property owners to easily access and update property data. Therefore, assessment mailing dates and appeal dates are subject to change. Please plan accordingly. Information will be published as it becomes available.

As new townships are certified, those dates will be published below.

Our phone lines remain open to the public during normal business hours and assistance is available via our website and social media channels.

Note that values may take 24 hours to update online from the mail / certified date. Result letters will be sent in the mail or sent to practitioners via GovQA in the few days after certification.

2021 Assessment Calendar: Suburbs (North, South, and West)

In the North Suburban and South and West Suburban townships, individual properties will only be reassessed only if there is a change due to division work, permit applications, or other special applications.

Note that values may take 24 hours to update online from the mail date.

+ These townships are certified by the Board of Review but the data is not yet available on the CCAO website due to the need to transfer the data from the mainframe used by the Board into the new, modern assessment system of record used by the CCAO.

Past Calendars:

2020 Assessment Calendar and Deadlines

2019 Assessment Calendar and Deadlines

2018 Assessment Calendar and Deadlines 

Other relevant information:

2022 CCAO Appeal Rules
2022 Practitioners Meeting Presentation Slides >> and Video >>
Commercial real estate participants: Market Analyst Day Presentations
Submit RPIE valuations data