Our analysis of every residential appeal filed in Gwinnett County during 2025 reveals an 82.1% success rate and $15,600 median reduction.
Gwinnett County homeowners filed 20,229 property tax appeals during the 2025 tax year, challenging a combined $410.7 million in assessed value. That's not an estimate from a survey or a projection from sample data. It's every single residential appeal on file, obtained through a public records request to the Gwinnett County Board of Tax Assessors.
The results paint a clear picture for anyone wondering whether filing an appeal is worth the effort. Of the 17,325 appeals that have closed, 82.1% received a reduction. The median successful appeal knocked $15,600 off the home's assessed value, and 84.2% of those winners locked in that lower assessment for three full years.
With 2026 assessment notices arriving in the coming weeks, this data can help you make an informed decision about whether to appeal, what evidence to submit, and what to realistically expect.
Of the 17,325 appeals that reached a final resolution, 14,234 received a reduction in assessed value. That's an 82.1% success rate. Another 3,034 appeals (17.5%) resulted in no change, and just 56 appeals (0.3%) saw their assessed value increase.
Of 17,325 closed appeals in Gwinnett County during the 2025 tax year, 82.1% received a reduction in assessed value. Only 56 appeals (0.3%) resulted in an increased assessment.
The fear that filing an appeal could backfire and raise your assessment is one of the most common reasons homeowners don't file. The data shows that risk is nearly nonexistent. Fifty-six increases out of 17,325 closed appeals means you'd have a 0.3% chance of seeing your value go up. By comparison, you'd have an 82.1% chance of getting it lowered.
At the time this data was pulled, 2,904 appeals (14.4% of the total 20,229 filed) were still open and working through the process. All outcome statistics in this article are based on the 17,325 closed appeals.
Most Gwinnett County property tax appeals never reach a hearing. 63% are resolved at the Assessor level, where the county's own staff reviews your appeal and adjusts the value. The success rate at that stage is 97.6%.
63% of Gwinnett County appeals are resolved at the Assessor level with a 97.6% win rate, meaning most homeowners never set foot in a hearing room.
Note: the table above shows where appeals were ultimately resolved, not a required sequence. After the Assessor's initial review, taxpayers choose one of three paths: Board of Equalization, Hearing Officer, or Arbitration. These are parallel options, not sequential steps.
This pattern makes sense when you understand the process. After you file your PT-311A form, the county assessor's office reviews your appeal first. If they agree your assessed value is too high, they issue a revised value. You can accept it, and the appeal is done.
The data suggests the county assessor's office is willing to make adjustments on most appeals it reviews. The drop-off in win rates at the Board of Equalization (33.2%) tells you something important: appeals that the assessor's office doesn't resolve are the harder cases. If you're headed to a BOE hearing, your odds are meaningfully different from the overall 82.1% number.
Settlement conferences, which are required by statute when either party appeals a BOE decision to Superior Court, show a 56.6% win rate with a notably higher median reduction of $41,800. Hearing Officers, who handle non-homestead properties valued above $500,000, resolved 309 appeals with a 99.4% win rate and a $182,500 median reduction. Those numbers reflect the self-selected nature of cases that reach this level, not a guaranteed outcome of escalation.
The median reduction among successful appeals was $15,600. The average was higher at $28,856, pulled up by large reductions on high-value properties. The median gives you a better picture of the typical outcome.
Two patterns stand out. First, the median reduction percentage is remarkably consistent at roughly 3% across every value tier. A $400,000 home and a $900,000 home both see about a 3% reduction when they win. The dollar amounts differ because the underlying values differ.
Second, win rates climb with home value. Homes valued over $1 million won 85.9% of the time compared to 78.4% for homes under $300,000. Even at the lowest tier, though, nearly four out of five appeals succeeded.
More than half of all appeals (53.6%) came from the $300,000 to $500,000 range, which lines up with the county's median certified value of $453,500.
Gwinnett County's combined millage rate is approximately 34.86 mills. Georgia's assessment ratio for residential property is 40%. To estimate annual tax savings:
84.2% of successful appellants received the three-year assessment freeze under O.C.G.A. 48-5-299(c). A typical $15,600 median reduction translates to roughly $651 in total tax savings over three years.
The three-year freeze is a significant part of the appeal's value. Of the 16,838 appeals with freeze data, 14,173 (84.2%) received the freeze. Only 2,665 (15.8%) had the reduction applied to the current year only. Under O.C.G.A. 48-5-299(c), when a successful appeal results in a value reduction, that lower value is generally locked in for the current year plus two additional years unless there's a qualifying change to the property.
Win rates vary meaningfully across Gwinnett County's cities, ranging from 96.1% in Auburn to 56.1% in Stone Mountain. Your specific location within the county does affect your odds.
Lawrenceville generates more appeals than any other city by a wide margin. Its 4,510 appeals represent 22.3% of every appeal filed in Gwinnett County. That concentration likely reflects the city's large population and its position as the county seat, not a signal that assessments are worse there specifically.
Peachtree Corners and Hoschton stand out for their high median reductions ($27,100 and $26,900 respectively), driven by their higher median home values ($698,800 and $655,700). Meanwhile, Stone Mountain's 56.1% win rate is a clear outlier. It's the only city where fewer than three-quarters of appeals succeed. Stone Mountain also has the lowest median home value ($348,800) and the smallest median reduction ($10,400) among the top 15 cities.
The broader pattern: higher-value areas tend to see both higher win rates and larger dollar reductions. But even the lowest-performing city still sees more than half of its appeals succeed.
Almost all Gwinnett County appeals are filed within two months of receiving their assessment notice. The 2025 notices were mailed on May 23, 2025.
96.9% of all appeals were filed in June and July. July actually edged out June, suggesting many homeowners wait until closer to the 45-day deadline. The 594 appeals filed in May came from homeowners who acted immediately after receiving their notice. Only 36 appeals trickled in outside this window.
The median appeal took 71 days from filing to resolution, roughly 2.5 months.
Half of all appeals were done within 71 days. The fastest 25% resolved in under 55 days. If your appeal stretches beyond four months (120 days), you're in the slower quarter, likely because it escalated to a BOE hearing or beyond.
This is where the data gets actionable. A closer look at roughly 7,400 appeals with analyzable filing data reveals which types of evidence produce the strongest results, and the answers are counterintuitive.
First, the baseline: of the appeals in the analyzable subset, roughly 80% were filed without attached supporting evidence on the PT-311A form. That doesn't necessarily mean those homeowners had no evidence at all. Many may have presented evidence verbally at a later BOE hearing or submitted materials separately. But the filing itself contained no documentation.
Even so, the difference between filing with and without attached evidence is notable.
Appeals filed with attached supporting evidence achieved an average reduction of 8.56%, compared to 6.37% for those without, a 34% improvement in outcomes.
The most effective evidence types are the ones homeowners use least. Assessment error arguments, where you identify factual mistakes in the county's records (wrong square footage, incorrect bedroom count, nonexistent features), produced an average reduction of 17.1%. That's 151% above the 6.8% baseline. But only 1.4% of classified appeals used this approach.
Assessment error arguments, used in only 1.4% of classified appeals, produced an average 17.1% reduction, more than double the baseline. The most powerful arguments are the ones almost nobody uses.
The contrast between what homeowners actually submit and what works best is striking. Sales comps are the most common evidence type (28.8% of classified appeals), but they only produce an 18% improvement over baseline. Meanwhile, the top three strategies (assessment errors, characteristic differences, and appeal letters) each outperform sales comps by wide margins, yet together they appear in only about 12% of appeals.
Characteristic differences arguments focus on how your home's specific features compare unfavorably to the county's comparable properties. Maybe your home backs up to a busy road while the comps don't, or your kitchen was last updated in 2005 while the comps were renovated recently. This approach achieved a 12.9% average reduction.
Appeal letters that make a structured, written case for a lower value appeared in only 6.7% of appeals but showed up in 26.1% of high-value appeals (those achieving over 30% reductions or more than $5,000 in tax savings). Formal letters were four times more common among top performers.
The sophistication of your submission correlates with results.
Complete packets (a structured appeal letter, supporting comps, and organized documentation) achieved an 11.2% average reduction. Freeform submissions, the most common DIY format, achieved 7.3%. That's a 53% gap between the most polished and the most casual approaches.
You don't need to hire a professional to bridge that gap. Moving from a freeform submission to structured text with a spreadsheet (the "semi-professional" tier at 8.0% to 8.5%) is something most homeowners can do on their own with the right template.
If you're going to include photos, what you photograph matters more than the fact that you included photos at all.
Exterior photos are the most commonly submitted type (16.0% of classified appeals), but they produce the second-lowest impact. Condition photos showing deferred maintenance, wear, and aging elements that reduce your home's value relative to the county's assessment performed best at 8.9%. Interior photos and yard photos also outperformed exterior shots.
The takeaway: a photo of your kitchen's dated countertops or your aging HVAC system tells a more useful story than a generic shot of your home's front.
The type of professional you hire matters more than whether you hire one at all. Tax firms matched DIY homeowners at 7.8%, while attorneys achieved 12.8%, suggesting the advantage comes from argument strategy rather than simply having representation.
The overall split in Gwinnett County is roughly even: about 48.3% of appeals were filed by homeowners themselves, and 51.7% were filed by professional preparers of some kind.
Attorneys achieved a 12.8% average reduction, 64% higher than the DIY average of 7.8%. Tax firms achieved the same 7.8% average as DIY homeowners. The type of representation matters far more than whether you have representation at all.
Attorneys are the standout. Their 12.8% average reduction is 64% higher than the DIY baseline and meaningfully above every other preparer type. Appraisers come in second at 9.7%, a 24% improvement. Tax firms and realtors performed at or slightly below the DIY average.
What explains the attorney advantage? The evidence data points to argument strategy. Attorneys are more likely to identify assessment errors and characteristic differences, the two highest-impact evidence types. They also tend to submit fewer but more focused documents (an average of 1.9 files versus 2.3 for DIY filers). Quality and argument selection, not volume, appear to drive the difference.
For homeowners weighing whether to hire help, the data suggests asking a specific question: will this professional help me build a stronger argument, or are they just filing the same paperwork I would? The answer depends on the type of professional and their approach to your specific situation.
Gwinnett County has approximately 308,000 assessed properties. The 20,229 appeals represent a 6.6% appeal rate, well above Georgia's statewide average of roughly 2.7%. Still, that means 93.4% of Gwinnett homeowners accepted their assessment without challenge.
Given the 82.1% success rate among those who did appeal, a significant number of homeowners are likely overpaying. Even a conservative estimate suggests tens of thousands of properties could benefit from an appeal but never file one.
The timing data reinforces this. 96.9% of appeals arrived in June and July, immediately following the May notice mailing. If you miss that window or simply don't get around to it, you've accepted whatever the county says your home is worth for the year.
The statistics in this article are drawn from complete 2025 tax year appeal records obtained through a public records request to the Gwinnett County Board of Tax Assessors. The dataset covers 20,229 residential property tax appeals filed on "Value" grounds with a valuation date of January 1, 2025.
Outcome statistics (win rates, reductions, resolution stages) are based on the 17,325 appeals that had reached a final resolution at the time of data collection. The remaining 2,904 open appeals (14.4%) are excluded from outcome calculations.
Evidence effectiveness data comes from an analyzable subset of roughly 7,400 appeals. Within that group, 1,492 (20.1%) included attached documentation on their PT-311A filings, and 5,925 (79.9%) did not. Of the appeals with documentation, 1,471 were classifiable by evidence type, document sophistication, and photo category. The "without evidence" category refers to appeals filed without attached documentation on the form itself, not necessarily to the absence of evidence at all stages of the process.
Preparer type performance data is drawn from 1,451 of the 1,471-appeal classified subset where preparer information was identifiable from the filing records.
Tax savings estimates use Gwinnett County's combined millage rate of approximately 34.86 mills and Georgia's 40% residential assessment ratio.
These records were obtained through a public records request to the Gwinnett County Board of Tax Assessors.
The 2025 data from 20,229 appeals tells a consistent story. The vast majority of homeowners who challenge their assessments get a reduction. Most of those reductions happen at the Assessor level without a hearing. And the three-year freeze multiplies the value of a successful appeal.
The evidence section may be the most useful part of this analysis for anyone preparing an appeal. The data shows that argument strategy matters more than volume. Finding an actual error in your property record, identifying meaningful differences between your home and the county's comps, or writing a structured appeal letter all outperform the most common approach of simply submitting comparable sales.
Whether you file on your own or work with a professional, the data points to the same conclusion: knowing what to argue, and documenting it clearly, gives you the strongest shot at a fair assessment.