Cobb County Property Tax Appeal: Deadline, Process, and the 299(c) Freeze

Cobb County mailed 2026 Annual Notices of Assessment in late April or early May, giving property owners until July 20, 2026 to file an appeal. Cobb has held its General Fund millage rate at 8.46 mills since 2018 — the longest uninterrupted freeze of the four major metro Atlanta counties. The total unincorporated rate for 2026 is 30.13 mills.

One thing that sets Cobb apart: the online appeal option goes through qpublic (Schneidercorp), and Cobb’s own instructions call it a “courtesy” and advise filing early in case of system issues. Mail or in-person is the reliable path if you are near the deadline.

Cobb County at a glance

How Georgia property tax assessments work

Georgia assesses property at 40% of fair market value as of January 1 each year. That 40% figure is called the assessed value. Your tax bill multiplies assessed value (after exemptions) by the combined millage rate from the county, school district and city.

The Board of Tax Assessors (BTA) sets the value. The Board of Equalization (BOE) — a separate, independent panel of three citizens — hears your appeal if the BTA does not resolve it.

In Cobb County, 40% of a $373,700 median home is $149,480 assessed value. At 30.13 mills total unincorporated, that is $4,503 before exemptions. Cobb County offers a floating homestead exemption that limits the annual growth in a homesteaded property’s assessed value to the prior year’s rate of inflation. In practice this functions like Georgia’s regular homestead rules but is county-specific. For unincorporated homesteaded owners, the effective rate after the standard exemption and Cobb’s floating exemption is around $3,300 on a $400,000 home.

The 299(c) three-year freeze: why one appeal covers three tax years

Under O.C.G.A. § 48-5-299(c), when your appeal results in an actual reduction in assessed value, the county cannot raise that value during the next two years. The appeal year plus two more = three years of protection. That is what turns a single appeal win into three years of lower bills.

The “actual reduction” requirement matters. Under HB 581 (2024), a “no change” outcome no longer triggers the freeze. If you appeal, come with evidence that supports a lower number, not just an argument that the current value is debatable.

Cobb’s floating homestead exemption already provides some protection for owner-occupied residential properties. But it does not protect rentals, commercial parcels or any property that does not carry a homestead exemption. For those owners, the 299(c) freeze from a successful appeal is the only protection against annual reassessment.

How to file in Cobb County

Step 1 — Request an informal review

Contact the Cobb County Board of Tax Assessors at 770-528-3100 or CobbTaxAssessor@cobbcounty.gov. Record errors get fixed fastest here. The review does not extend the 45-day deadline.

Step 2 — File the PT-311A by July 20

File online via the qpublic portal at qpublic.schneidercorp.com (search your property, click “Appeal to the Board of Assessors,” click “Approve and submit this appeal”); by mail to Cobb County Board of Tax Assessors, P.O. Box 649, Marietta, GA 30061 (USPS postmark required); or in person at 736 Whitlock Ave NW, Suite 200, Marietta, GA 30064. Cobb treats the online option as a convenience; if you are near the deadline, mail certified or hand-deliver. No email, no fax. Any letter that identifies the property (address + parcel ID), states your appeal, and includes your chosen route is acceptable.

You must choose a route on the form: BOE (most common, no fee), arbitration, or hearing officer. If you choose the equity/uniformity argument, note it on your PT-311A and choose BOE (arbitration does not permit uniformity appeals).

Step 3 — BTA review, amended notice, and BOE

After review, the BTA may issue an amended notice with a revised value. Accept it or let the appeal continue to the BOE. The hearing is short, evidence-driven, and before a three-citizen panel. The BOE’s written decision is mailed by certified or overnight delivery.

Step 4 — Pay your taxes while the appeal is pending

Georgia law requires payment of the undisputed amount while an appeal is open. Cobb issues a temporary bill. Pay it and preserve your appeal rights.

What will not work here

• The wrong date. Georgia values property as of January 1. Sales after that date and damage after that date are next-year issues.
• Millage rates. The BOE hears value and uniformity. It does not set tax rates. Budget-hearing complaints go to the Board of Commissioners.
• “My bill went up too much.” A higher bill can mean a higher assessed value, a higher millage, a lost exemption, or all three. Identify the cause before deciding whether to appeal.
• Filing after the deadline. Georgia law does not extend the 45-day window. One day late means waiting until next year.

Who should appeal in Cobb County

• Owners whose January 1 value exceeds comparable sales. Three to five closed sales near January 1, adjusted for condition, size and subdivision.
• Recent buyers. Closing price near January 1 is very strong evidence.
• Owners whose assessed value per square foot is above similar Cobb properties. Uniformity argument under § 48-5-299(c). Pull comparable assessments from the county records, not sales prices.
• Rental and commercial owners. Cobb’s floating exemption does not protect non-homestead properties. Every year of overassessment is unrecoverable.

If you would rather not build the comparable-sales analysis yourself, TaxDrop One runs your Cobb County property against public records and MLS-sourced sales, identifies whether you have a case, and delivers a filled PT-311A with the evidence packet for $129 per property per tax year. A licensed appraiser reviews every Georgia case before it goes out.

More on the county: Cobb County property tax appeals. Georgia statewide: Georgia property tax appeals.