How Taxes Are Calculated
The ad valorem tax (or property tax) is the primary source of revenue for local governments in Georgia. Ad valorem means "according to value."
Ad valorem taxes are calculated using the following formula:
(Fair Market Value x 0.4) x (Millage Rate/1,000) = Ad Valorem Tax
The first part of the formula, (Fair Market Value x 0.4), describes how the assessed value of the property is calculated. The county Board of Tax Assessors, which is appointed by the county Board of Commissioners, assesses all property for tax purposes. Assessments are by law based upon 40% of the fair market value as of January 1 each year.
A mill is 1/10 of 1 cent or $1 per $1,000 of assessed value. When we publish the millage rate, we are describing the number of mills. When we calculate taxes, we divide the number of mills by 1,000 to convert mills into whole dollars.
The millage rate is approved by each taxing authority. The county Board of Commissioners sets the millage rate for county taxes, the county Board of Education sets the millage rate for county school taxes and the city authorities determine the rate for city taxes. These rates are generally set and approved in late July.
All property taxes are calculated in the same way for real property, personal property, heavy duty, mobile home and public utility. Taxes for automobiles can be calculated either under the Ad Valorem tax (all cars purchased prior to 2013) or TAVT tax.
City & Timber Taxes
Acworth, Austell, Kennesaw, Marietta, Smyrna and Powder Springs collect their own city taxes. For tax information, contact the city tax department directly.
Standing timber is assessed for ad valorem taxation only once, at the time of harvest or sale, separate and apart from the underlying land. Such timber is assessed at 100% of its fair market value.
Tax Bills & Payments
Cobb County tax bills are mailed each year by August 15 and are due by October 15. Payments can be made online, in-office and via mail. All mailed payments must be postmarked by the October 15 deadline. We do not accept metered or kiosk postmarks as proof of timely mailing.
If you lost your bill, we can mail you a new one. To do so, we need the parcel ID for your property. You can also reprint your bill online and attach it to your payment if you wish to use a physical check or money order.
Please note: Any subsequent adjusted bills and appeal bills, as necessary, are mailed out throughout the year depending on the situation.
The cities of Acworth, Austell, Kennesaw, Marietta, Smyrna and Powder Springs handles the billing of city property taxes for their respective cities. If you own property inside the city limits of one of the cities, then you should expect to receive a Cobb County tax bill and a city tax bill for that property.
2023 Property Tax bills were issued on August 11, 2023, and are due by October 15, 2023. Payments must be received or USPS postmarked by the due date to be considered on time.
Understanding Your Tax Bill
Each property tax bill is formatted in the same way. Knowing how to read your tax bill will give you a better idea of your current exemption status, your parcel ID and your tax district, amongst other items.
Below is a sample of your tax bill. Click the image to learn more about the different sections of the bill.
Ways You Can Pay Your Taxes
We offer a number of ways for you to pay your property taxes:
We accept e-checks, Visa, Mastercard, Discover, American Express, PayPal and PayPal Credit. Convenience fees for debit and credit cards will apply. There are no convenience fees for paying by e-check.
You can mail in your payment with a check or money order. Make checks payable to the Cobb County Tax Commissioner.
Send your payment to:
Cobb County Tax Commissioner
P.O. Box 100127
Marietta, GA 30061
In-Person or Phone
You can pay in-person at any of the following locations:
- Property Tax Division at 736 Whitlock Ave in Marietta
- East Cobb Office at 4400 Lower Roswell Rd in Marietta
- South Cobb Government Service Center at 4700 Austell Rd in Austell
You can also use our automated system by phone at 1-866-PAY-COBB (1-866-729-2622) (processing fees applicable depending on payment selection).
Typically, your mortgage company will have an escrow account set aside for paying property taxes. Once this account is established, they send us a notice stating they will be paying your property taxes. We then send both you and your mortgage company a bill each year.
Although your mortgage company offers you the convenience of paying your property taxes, ultimately you must ensure your taxes are paid on time no matter who is handling the payment. In the event you both pay taxes on the same property, we will refund the overpayment back to the payer.
Partial & Late Payments
Partial payments are accepted if you are unable to pay your bill in full. However, if your bill has an outstanding balance by the time your taxes are due on October 15, we will apply late fees and interest to the remaining balance. Paying some of your taxes is always better than paying none of your taxes.
Payments made after October 15 are considered late. As a result, you will be charged:
- 5% of your taxes
- Interest every month you are late
If you do not pay your taxes at all, your property may be subject to a Fi. Fa. (tax lien) and eventually put up for tax sale. Find out more about Fi. Fa.'s and tax sales on our delinquent taxes page.
If your property is subject to a Fi. Fa. you will also be charged:
- $23.00 on taxes less than $100.00
- Or $33.00 on taxes greater than $100
- Any administrative fees associated with issuing the Fi. Fa.
Can Late Fees be Waived?
Unfortunately, late fees cannot be waived. If you did not receive your tax bill, you can always print your bill online or contact us.