How to Appeal Your Cobb County Property Tax Assessment
How Do You Appeal a Cobb County Property Tax Assessment?
To appeal your Cobb County property tax assessment, file within 45 days of the date on your assessment notice — online at assessor.cobbcounty.gov/appeals/ or by mailing Form PT-311A to P.O. Box 649, Marietta, GA 30061. Your case goes before the Board of Equalization, where you'll present comparable sales, condition evidence, or a recent appraisal. Win the appeal, and your reduced assessed value is locked in for three years under Georgia law.
- You have 45 days from the mailing date on your notice — not the date you received it
- File free at assessor.cobbcounty.gov/appeals/ or mail Form PT-311A to P.O. Box 649, Marietta, GA 30061 — no attorney required, no filing fee
- Strongest evidence: 3–5 comparable sales from the past year, condition photos, or a licensed appraisal completed within 9 months of the assessment date
- Over 60% of Cobb County residential appeals with proper evidence result in a reduced assessment
- Win the appeal and Georgia locks your lower assessed value in for three years — worth $1,700–$1,900+ in savings on a $500K home
If a Cobb County assessment notice landed in your mailbox and your first reaction was "that can't be right" — you're not alone. Assessors use mass appraisal models. They don't walk through your home. They don't see the water-damaged basement, the original 1990s kitchen, or the fact that your lot backs up to a busy road. And in a market where values have climbed sharply, they frequently overshoot.
Here's the good news: you have the right to appeal. More than that — over 60% of Cobb County homeowners who file with proper evidence come away with a reduced assessment. And if you win, Georgia locks that lower value in for three years.
The window is 45 days from the date on your notice. Not 45 days from when you opened it. The clock started when it was mailed.
Why a Cobb County Property Tax Appeal Is Worth More Than You Think
Most homeowners assume an appeal is a long shot — a bureaucratic headache with a modest annual payoff. The math tells a different story.
In Kennesaw, a $500,000 home carries an estimated annual property tax bill of roughly $5,800–$6,200 before exemptions. A successful appeal that reduces your assessed value by just 10% saves $580–$620 per year. On its own, that's real but modest.
Here's what most people miss: Georgia law requires the county to freeze your reduced assessed value for three years once an appeal succeeds. The county cannot increase your assessed value during that window unless you make structural changes to the property. That means one afternoon of preparation translates to three years of lower bills.
On a $500K home with a 10% reduction, that's up to $1,860 in total savings from a single appeal.
If you're planning to sell in the next year or two, a lower assessed value also works in your favor with buyers who are running monthly cost numbers carefully. For a full picture of what those costs look like right now, see the breakdown of Kennesaw property taxes and insurance in 2026 — it covers what buyers are actually budgeting for this year.
The Cobb County Property Tax Appeal Process, Step by Step
Step 1 — Read Your Assessment Notice Carefully
Your Annual Notice of Assessment shows your property's fair market value as determined by the Board of Tax Assessors and the assessed value used to calculate your tax bill (40% of fair market value in Georgia). Check the mailing date on the notice — that's when your 45-day window begins.
Before assuming the value is wrong, confirm the basics: Is the square footage correct? Are your exemptions already applied — homestead, senior school tax, or any others you've previously filed for? Sometimes the issue is a data error rather than a valuation dispute, and those can often be resolved without a formal appeal.
Step 2 — Decide Your Grounds for Appeal
Georgia recognizes three valid grounds for a property tax appeal:
- Value — you believe the assessed value is higher than the property's fair market value
- Uniformity — your property is assessed higher than comparable properties in your area
- Taxability — you believe the property is not taxable or qualifies for an exemption not currently applied
The vast majority of residential appeals are filed on value grounds, supported by comparable sales data or a recent appraisal.
Step 3 — File Your Appeal
You have two options:
- Online: Go to assessor.cobbcounty.gov/appeals/ and click the "Appeal to Board of Assessors" button. Enter your email to receive a unique link and code to complete the filing.
- By mail: Download Form PT-311A from the Georgia Department of Revenue, complete it, and mail to: Cobb County Board of Tax Assessors, P.O. Box 649, Marietta, GA 30061.
There is no filing fee. No attorney required. If you're mailing, send it certified with return receipt — the 45-day deadline is strictly enforced, and you'll want proof of the postmark date.
Step 4 — Gather Your Evidence
After filing, you'll receive a scheduled hearing date with the Board of Equalization. Use the window between filing and your hearing to build your case. (See the section below on what evidence actually works.)
Step 5 — Attend Your Board of Equalization Hearing
The Board of Equalization (BOE) is a panel of three local citizens — not attorneys, not county employees. You'll present your evidence. The Cobb County assessor's office presents theirs. The panel considers both and issues a written decision by certified mail within 10 days of the hearing.
The hearing is informal. You can represent yourself. Bring printed copies of your comparables, photos, and any appraisal or contractor estimates. Being organized and prepared matters more than legal expertise.
Step 6 — If the BOE Doesn't Rule in Your Favor
You can appeal the BOE's decision to Cobb County Superior Court within 30 days of receiving the decision letter. For most residential properties, this step isn't necessary — but it's available if the stakes justify it.
What Evidence Actually Wins Cobb County Tax Appeals
Comparable Sales — Most Common and Most Effective
The Board of Equalization responds to data. Pull 3–5 closed sales of homes similar to yours from the 6–12 months prior to January 1 of the tax year you're appealing — that's Georgia's official valuation date for all property tax assessments.
Look for comparables that are:
- Within the same subdivision or street, if possible
- Within ±10–15% of your home's square footage
- Similar in bedroom/bathroom count, lot size, and major features (garage, basement, pool)
- Arm's-length, open-market sales — not foreclosures, short sales, or family transfers, which may not be accepted as valid comparables
In Marietta and Kennesaw, values can swing $50,000–$100,000 based on condition, lot position, and age of updates. A comp that sold for $430,000 while your home is assessed at $500,000 — both 2,400-square-foot colonials built in 1995 — is compelling evidence that the assessor's number is off.
A local real estate agent can pull a Comparative Market Analysis (CMA) quickly and target it to the right criteria. It's often more precise and credible than pulling comps from Zillow on your own.
Property Condition Documentation
Did the assessor walk through your home? Almost certainly not. Mass appraisal models use aggregate neighborhood data — they don't account for the original HVAC system running on borrowed time, the roof at the end of its useful life, or the unfinished basement that needs $35,000 in work before it's livable.
Document condition issues with photos and written estimates from licensed contractors. A quote showing $20,000–$30,000 in deferred repairs is meaningful evidence that your home isn't worth the same as the fully updated comparable three streets over.
A Licensed Appraisal
The strongest possible evidence is a recent appraisal by a Georgia-licensed real estate appraiser, completed no more than nine months before the date of the assessment. An appraisal typically runs $350–$500 for most Cobb County homes.
Not every appeal needs one. If comparable sales tell a clear story on their own, you may not need the added expense. But for higher-value properties where the annual savings justify the cost, an appraisal is the cleanest, most credible evidence you can bring to the hearing.
Frequently Asked Questions
What is the deadline to appeal a Cobb County property tax assessment?
You have 45 days from the date your Annual Notice of Assessment was mailed — not the date you received it. For 2026, Cobb County assessment notices are arriving in late May to early June, putting the appeal deadline in mid-July for most homeowners. Missing this window means waiting until next year's assessment cycle to challenge the value.
What grounds can I use to appeal my Cobb County property tax assessment?
Georgia allows appeals on three grounds: value (the assessment is higher than fair market value), uniformity (your property is assessed higher than comparable properties nearby), and taxability (the property shouldn't be taxed or qualifies for an exemption). Most residential appeals are filed on value grounds, supported by comparable sales or a recent appraisal.
What happens at a Board of Equalization hearing in Cobb County?
The Board of Equalization is a panel of three local citizens — not assessors or attorneys. You'll present your evidence, the county assessor's office presents theirs, and the panel issues a written decision by certified mail within 10 days. The hearing is informal and you can represent yourself. If you're buying or selling in Acworth or the broader West Cobb area, understanding how assessments affect carrying costs is worth building into your planning.
How much could I save if I win my Cobb County property tax appeal?
On a $500,000 home in Kennesaw, a 10% reduction in assessed value saves roughly $580–$620 per year. Because Georgia locks in your reduced value for three years after a successful appeal, the total impact is closer to $1,740–$1,860 — from a single afternoon of preparation and a free filing.
Do I need a lawyer to appeal property taxes in Cobb County?
No attorney is required, and there's no cost to file your initial appeal. Many homeowners represent themselves successfully with solid comparable sales data. Property tax consultants are worth considering for high-value or commercial properties — they typically charge a percentage of the first year's tax savings rather than an upfront fee. For most residential appeals, a well-prepared homeowner with 3–5 strong comparables has a legitimate shot at a favorable outcome.
Appealing your Cobb County property tax assessment isn't complicated — the form is free to file and the majority of properly documented appeals succeed. The harder part is knowing which comparables to pull, how to frame condition issues effectively, and whether your assessed value actually has a case to make.
If you're thinking about selling in Kennesaw or the broader West Cobb market, understanding your assessed value — and whether it's worth challenging before you list — is worth a conversation. A lower assessed value signals lower carrying costs to buyers who are doing the monthly math alongside their mortgage payment.
Schedule a consultation with me, Robert Masoudpour, Associate Broker at Atlanta Communities - West Cobb. I'll walk you through your specific situation — whether that means timing a sale around your assessment cycle, identifying the right comparables for a BOE hearing, or simply understanding what your home is worth in today's market.
