Your Georgia tax bill comes down to four steps and one key number: 40%.
How to Calculate Your Georgia Property Tax Bill (Simple Formula) If you want to calculate your property tax bill in Georgia, the math comes down to four steps: find your fair market value, multiply by 40%, subtract your exemptions, then multiply by the millage rate. That's it. But the details behind each step matter — and a mistake at any point can leave you either confused about your bill or overpaying for years without realizing it. This walkthrough covers the full formula with a real Gwinnett County example using 2025 rates, including a breakdown of every layer of millage that stacks onto your bill. What Are the Key Terms You Need to Know? Before running the numbers, four terms form the foundation of every Georgia property tax bill. Fair Market Value (FMV) is the price a knowledgeable, willing buyer would pay a willing seller in an arm's-length transaction, as defined under O.C.G.A. § 48-5-2. Your county assessor estimates this every year as of January 1. Assessed Value is 40% of your FMV. Georgia law (O.C.G.A. § 48-5-7) requires all residential property to be assessed at 40% of market value — not 100%, not some other number. This is the 40% assessment ratio that makes Georgia's system distinct. Taxable Value is what's left after you subtract any exemptions — homestead, senior, veteran, or others — from your assessed value. Millage Rate is the tax rate applied to your taxable value. One mill equals $1 of tax for every $1,000 of taxable value. A total rate of 30 mills means $30 per $1,000, or 3% of your taxable value (not your market value). How Do I Calculate My Property Tax Bill in Georgia? Here's the complete formula, step by step. Start with Fair Market Value. This is the assessor's estimate of what…