A property tax exemption is like a discount applied to your EAV. If you qualify for an exemption, it allows you to lower your EAV.Org to apply for a certificate of registration. Property tax exemptions are savings that contribute to lowering a homeowner's property tax bill. The most common is the Homeowner Exemption. The exemption application must be filed yearly. Join us for a workshop to learn about the Cook County Assessor's Office and homeowner exemptions. First-time applicants can obtain forms here Senior Homestead Exemption Form (pdf). Please read the instructions before completing this form. For electronic filing information, visit the MyDec Helpful Resource page.