One-third of Cobb County homes were overvalued in 2025, and the county opted out of Georgia's new tax cap at every level. Here's what your notice means.
Your Cobb County 2026 Assessment Notice Explained Cobb County assessment notices are expected to arrive in mid-to-late May 2026, and the numbers on them deserve careful attention. An estimated 33% of Cobb County homes were overvalued in 2025. Only 32% of residential properties were reassessed that year, but those that were saw a median increase of 8.59% (with an average jump of 20.49%). The county's overall tax digest growth slowed to 3.1%, down from 8.5% in 2024 and 13% in 2023, yet that headline figure masks the sharp increases concentrated on reassessed properties. Making matters worse, Cobb County opted out of HB 581's floating homestead exemption at every level. The county commission voted 4-0 against it, and the school district, Marietta, and all other cities followed suit. The county's existing floating homestead exemption provides some protection, but it does not cap assessed value increases the way HB 581 would have. With school taxes at 18.70 mills representing roughly 62% of the typical tax bill, even a modest overvaluation translates to real money. What the Numbers on Your Cobb County Assessment Notice Mean Georgia law requires all property to be assessed at 40% of its fair market value. Your county does not tax you on what your home is worth. It taxes you on 40% of that number, called the assessed value. If your county says your home is worth $400,000, your assessed value is $160,000. That $160,000 is what the millage rate applies to when calculating your tax bill. This ratio is set by state statute (O.C.G.A. 48-5-7) and applies uniformly across all 159 Georgia counties. It has been the standard for decades and is not subject to annual change. A handful of cities assess at different ratios (Dalton and Gainesville at 100%, Decatur at 50%), but these exceptions are…