CHICAGO – Cook County Assessor Joseph Berrios announced today that his office has once again extended the deadline for the Senior Citizen Exemption and Senior Freeze Exemption renewal applications and new applications for Tax Year 2017. The new extended application deadline is Monday, April 30, 2018. Any application postmarked by April 30^th, will be on time. (The original deadlines were February 7^th, later extended to March 2^nd and March 30^th.)