Cobb County 2026 Property Tax Bills: Dates, Payment, and Closings
Home Selling
Home Selling
Cobb County property tax bills land in the same window every year, and the deadline does not move. Bills are mailed by August 15 and payment is due on or before October 15. For homeowners that is a calendar item. For anyone buying or selling between August and December, it is also a closing item, because who actually pays the bill depends on the contract and the proration language rather than on whose name is printed on the envelope.
This is a process explainer covering dates, payment methods, penalties, and how the bill interacts with a sale. It is not tax advice. Confirm anything specific to your situation with the Cobb County Tax Commissioner and your own licensed tax professional.
Cobb County mails property tax bills by August 15 each year, and payment is due on or before October 15. The bill goes to whoever owned the property on January 1 of that tax year. That January 1 rule is why a seller can receive a bill for a house they no longer own, and it is the reason proration exists.
Taxes are due in full by October 15. The Tax Commissioner does accept partial payments, but penalty and interest accrue on whatever balance remains after the due date. Arrangements are handled by phone at 770-528-8600. Owners who want to spread the cost usually do it through a mortgage escrow account rather than through the county.
Payment must be received or bear a USPS postmark by the due date. Metered postmarks and kiosk postmarks do not qualify as proof of timely payment. If you are mailing close to the deadline, hand it to a postal clerk and get the counter postmark.
Cobb offers several channels, and the fees differ. Paying online by e-check carries no fee. Credit card, debit card, PayPal, Apple Pay, and Google Pay all carry convenience fees. You can also mail a check or money order to P.O. Box 100127, Marietta, GA 30061, pay by phone through the automated system at 1-866-535-2622, or pay in person at one of five county office locations.
Many mortgage servicers pay the bill directly from escrow. That does not mean you should ignore the bill. Confirm the payment posted before the deadline, because the penalty falls on the property and the owner, not on the servicer. The Tax Commissioner's property tax overview page lists every payment method and the current contact details.
A 5 percent penalty applies to anything unpaid after October 15, with additional interest each month until the balance is cleared. If the bill stays unpaid, the Tax Commissioner sends written notice, and if it remains unpaid 30 days after that notice an execution may issue. Fi. Fa. fees run $23.00 on taxes under $100.00 and $33.00 on taxes over $100. Liens and tax sale proceedings follow from there. None of that happens overnight, but all of it starts with a missed October date.
Cobb's official 2026 millage chart puts the county general rate at 8.46, fire at 2.97, and school at 18.70, for a total of 30.13 mills in unincorporated Cobb. City totals differ: Acworth 39.08, Austell 35.41, Kennesaw 39.28, Marietta 31.122, Powder Springs 39.63, Smyrna 36.15, and Mableton 30.13. Special districts include Mableton Public Safety at 34.63, Cumberland CID at 37.58, and Town Center CID at 35.13.
Two homes with identical assessed values on opposite sides of a municipal boundary can carry meaningfully different annual bills. That is not a comment on either place. It is arithmetic, and it belongs in a buyer's carrying cost analysis alongside insurance and any association dues. Buyers weighing addresses across jurisdiction lines will recognize the same theme in our piece on what an Acworth address actually means.
Cobb's Board announced its intent to increase taxes 4.07 percent over the rollback rate in the General Fund for 2026, with public hearings held at 100 Cherokee Street in Marietta on July 14, July 21, and July 28, 2026. The county noted that homestead exemption holders whose property value did not change would see no change in their county maintenance and operations bill, since the millage rate itself was unchanged from the prior year.
Exemptions reduce assessed value before the millage rate is applied, so they lower the base the rate multiplies against. Cobb's basic homestead exemption is $10,000 in the county general and county school general categories. It requires that you own and occupy the property as your primary residence, and all applicants must appear on the deed.
Applications must be received or USPS postmarked by April 1. Missing that date waives the exemption for that tax year. This is the single most common avoidable mistake for someone who bought a home the previous year: the exemption does not follow the property, it follows the owner, and it has to be applied for.
Cobb publishes several additional exemptions on its exemptions page, including a school tax exemption for owners age 62 and older, a $22,000 disability exemption with an income test, a state senior exemption at age 65 with an income limit, and exemptions for qualifying disabled veterans and certain surviving spouses. Each has its own eligibility test and documentation, and the right place to confirm eligibility is the Tax Commissioner's office rather than a general article.
In a normal Georgia residential closing, property taxes are prorated between seller and buyer as of the closing date, using either the current year bill if it has been issued or the prior year figures if it has not. The closing attorney handles the calculation. The two questions worth asking are which figure is being used and what happens if the actual bill differs.
A July closing usually prorates on prior year numbers because the current bill has not been mailed. If the new bill comes in materially higher, neither party is automatically made whole unless the contract says so. Ask your closing attorney how the proration is being calculated and confirm the answer in writing.
This is the cleaner scenario, because the actual bill exists. The credit is calculated against a real number, and the buyer typically becomes responsible for paying it by October 15. Sellers should not assume the closing attorney automatically pays the bill out of proceeds. Confirm it.
If your assessment is under appeal, you still have to pay at least the appeal amount by the due date to avoid the 5 percent penalty, with interest accruing monthly on the remaining balance. Owners who went through that process this year may want to revisit our guides on appealing a Cobb County property tax assessment and on 2026 appeal deadlines across Fulton, DeKalb, and Cobb.
Three questions cover almost all of it. Which tax year figures are being used for the proration and why. Does the seller have an exemption on file that inflated their bill downward and will not transfer to you. And is there a city bill in addition to the county bill for this address. That last question matters in Acworth, Austell, Kennesaw, Marietta, Powder Springs, Smyrna, and now Mableton, where a municipal levy sits alongside the county one.
A buyer's first full year is often the year the bill changes most, because the assessment may be revisited after a sale and because the prior owner's exemption is gone until the new owner files. Budgeting off the seller's old bill is the most common carrying cost mistake we see. Build the estimate off the assessed value and the current millage for the jurisdiction, then apply only the exemptions you will actually qualify for.
When are Cobb County property tax bills due? Bills are mailed by August 15 and payment is due on or before October 15. Bills are issued to the owner of record as of January 1.
Does Cobb County offer an installment plan? No. Taxes are due in full by October 15. Partial payments are accepted, but penalty and interest accrue on the unpaid balance after the due date.
What is the penalty for paying late? A 5 percent penalty plus additional interest each month until paid in full, followed by written notice and, if still unpaid 30 days later, a possible execution with Fi. Fa. fees of $23.00 or $33.00 depending on the amount.
When is the Cobb homestead exemption deadline? April 1. Applications must be received or USPS postmarked by that date, and missing it waives the exemption for that tax year.
The Cobb tax calendar is one of the few things in real estate that is genuinely predictable: mailed by August 15, due October 15, exemptions filed by April 1. Homeowners who put those three dates in a calendar rarely have a problem. Buyers and sellers who ask one direct question about proration at the contract stage rarely have one either.
Clareo Group, powered by The Agency Atlanta, works Cobb County every day and builds the tax and proration conversation into the transaction rather than leaving it to the closing table. Reach out and we will pull the current figures for your address and walk through what they mean for a sale, a purchase, or a hold.
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