The Assessor's office of Cook County has published the schedule for the reassessment of real estate property values for Chicago. The mailing dates for the reassessment's are as follows. The time for filing commercial tax appraisal and other documentation is short so you need to move quickly once the townships are released.

Rogers Park - 2/18/2015
Norwood Park - 3/3/2015
Lake View - 4/8/2015
Lake - 5/8/2015
Hyde Park - 6/16/2015
West - 7/17/2015
Jefferson - 8/14/2015
North Chicago - 9/14/2015
South Chicago - 10/5/2015