Property owners in DeKalb, Forsyth, and Fulton counties have 45 days from their assessment notice date to appeal property values. Deadlines are July 13 for DeKalb and July 31 for Fulton. Notices show assessed fair market value and exemptions but are not tax bills. Taxes are calculated using millage rates set after public hearings. Appeals can be made if values seem too high or inaccurate, with options for hearings or arbitration.