If you own commercial property in Florida, the county sets a value on it every January and your tax bill follows that number. You can challenge it. The path is short, the deadline is unforgiving, and the strongest argument is written into the statute itself. Here is how the appeal actually works, step by step, and what it takes to make the math win.
It starts with the TRIM notice in August
Every January 1 the county Property Appraiser sets a Just Value on your parcel — their estimate of market value. They did not walk your building; they modeled it with mass appraisal across thousands of properties at once. That is the number you can challenge, and mass appraisal is routinely wrong on any individual parcel.
You find out what they decided in mid-to-late August, when the TRIM notice (Truth in Millage) arrives. It lists your just value, your assessed value, and the taxes that follow. All 67 counties mail at roughly the same time. The TRIM notice is what starts the clock — read it the day it lands.
You have about 25 days to petition
To appeal, you file a DR-486 Petition with your county's Value Adjustment Board (VAB), along with a small filing fee (about $15). The deadline is roughly 25 days after the TRIM notice mails — the exact date is printed on your notice. Miss it and you wait a full year for the next cycle.
This single date is the most important one in the whole process. There is no grace period and no late filing. If you are weighing whether to appeal, decide before the deadline, not after. You can see the counties we read in full on the Florida hub, and the per-county detail — including Miami-Dade, where we re-check the live roll before anything is filed.
The legal lever: just value is net of the costs of sale
Here is the part most owners do not know. Under Fla. Stat. s.193.011(8), just value is not the gross price your building would sell for. The statute requires the Property Appraiser to deduct the usual and reasonable costs of sale — broker commission, legal fees, documentary stamps — customarily around 15%. So a correctly assessed building should sit at roughly 85% of what comparable buildings actually sold for.
If your assessment meets or exceeds the gross price comparable properties truly sold for, it cannot be net of the costs of sale the law requires. That is a statutory error the magistrate must consider — not a subjective "I think it is worth less" argument.
This is why the cost-of-sale lever is so clean. We are not asking the Value Adjustment Board to substitute one opinion of value for another. We are showing that the assessment, on its face, skipped a deduction the statute mandates.
Qualified arms-length sales are the evidence
The "what comparables sold for" number cannot come from a feeling. Florida's Department of Revenue publishes a public sale file — the same data the state uses for its own ratio studies. We pull qualified arms-length sales from it: real transactions between unrelated parties, screened for the qualification codes the state uses, with multi-parcel and outlier sales removed.
Then we adjust those comparables for size, age, and location before we ever say you have a case, because one sale is not a market and properties differ for real reasons. Only when your just value sits at or above what genuine comparables sold for — before the statutory cost-of-sale deduction — do we conclude you are overpaying. We do not name owners, and we do not guess.
The burden, and who carries it
Under Fla. Stat. s.194.301, the Property Appraiser's assessment carries a presumption of correctness — but that presumption can be overcome. If you present competent, substantial evidence that the assessment does not represent just value, the presumption is lost and the board weighs both sides on the record. Qualified sales showing the assessment is not net of the costs of sale is exactly the kind of evidence the statute contemplates. The case is then heard by a Special Magistrate — an independent appraiser or attorney — usually in a short hearing where each side presents its value and the magistrate rules.
What WinningAppeals does, and what your agent does
We read every commercial parcel off the county's own public roll, match it to qualified sales from the state's free file, run the size and age adjustments, apply the statutory cost-of-sale, and draft the DR-486 with the evidence packet. That is the model's job: find the case and build the argument from public records.
What the model does not do is file or represent you. A licensed, authorized Florida agent reviews the case, files the petition, and stands up at the hearing. The law requires a human to sign the petition, and we keep that gate strict: the AI proposes, a person approves and files. We are a new company and say so plainly — what we offer is the math and the public-record evidence behind it, not a promise.
You pay nothing up front. We work on contingency, and in our founding year the fee is 10% of your first-year tax savings — owed only if your value actually drops. Figures we share are derived from public records and adjusted comparables; they are an estimate of your case, not a guarantee of the outcome. If you want the broader picture across our states, the blog covers the Texas and Utah mechanics too.