Fill out the Homestead Tax Credit, 54-028 form. Return the form to your city or county assessor.You must file your homestead exemption application with your county tax officials. Eligible claimants who are 65 years of age or older on or before January 1 of the assessment year are now eligible for a homestead tax exemption. Douglas County has additional exemptions. New applications for homestead tax credit are to be filed with the Assessor on or before July 1 of the year the credit is first claimed. I declare residency in Iowa for purposes of income taxation and that no other application for homestead credit or exemption has been filed on other property. Because of this, your property tax bill would be lower.