Rob Hartley

Founder, AppealDesk · February 11, 2026

Property Tax Appeal Deadlines by State: The Complete 2026 Calendar

Updated February 2026 · 15 min read

Why Deadlines Matter More Than You Think

The appeal deadline is the single biggest reason homeowners overpay property taxes. Not because they don't have a case — but because they didn't act in time.

According to U.S. Census Bureau data, American homeowners pay over $600 billion in property taxes annually — and missed deadlines are one reason overassessments persist. Here's what makes property tax deadlines uniquely punishing: in most states, the deadline falls before you receive your actual tax bill. You're expected to act on the assessment notice — the document that tells you what the county thinks your home is worth — not the bill that tells you what you owe. By the time the bill arrives, the window to challenge it has already closed.

Courts consistently uphold these deadlines with no exceptions. Filing one day late is treated the same as not filing at all. And in states with multi-year reassessment cycles — like Illinois (triennial in Cook County) or Maryland (triennial groups) — a single missed deadline can lock you into an overassessment for two to three years.

The deadlines themselves vary wildly. Florida gives you just 25 days from your TRIM notice. Oregon's deadline is December 31. Some states use a fixed calendar date; others start the clock when your notice is mailed. Some tie the deadline to a board meeting that shifts year to year. The Lincoln Institute of Land Policy's Significant Features of the Property Tax database is the most comprehensive source for comparing these rules across all 50 states.

One thing that adds confusion: as the International Association of Assessing Officers (IAAO) notes, states don't even call the process the same thing. If you're in Texas, you “protest.” In New York, you “grieve.” In Colorado, you file an “objection.” Everywhere else, you “appeal.” Same process, different name — don't let the vocabulary trip you up.

2026 Property Tax Appeal Deadlines by State

The table below lists the appeal deadline for every state and DC. “Deadline Type” tells you whether the date is the same every year (Fixed), triggered by your notice (Rolling), set by your county (Variable), or tied to a board meeting (Board Session).

Deadlines change. Always verify with your county assessor's office before relying on any date below.

Understanding the Four Types of Deadlines

Not all deadlines work the same way. Understanding which type your state uses determines how you track it and how much time you actually have.

Fixed-Date Deadlines

The easiest to track — the same date every year, regardless of when your notice arrives. Texas's May 15, Ohio's March 31, and Massachusetts's February 2 are all fixed dates. The risk: because the date seems far away, it's easy to procrastinate until it's too late to gather evidence. Start preparing as soon as your assessment notice arrives, not when the deadline approaches.

Rolling Deadlines (Days from Notice)

The clock starts when your assessment notice is mailed, not on a universal date. Florida gives you just 25 days from your TRIM notice. Georgia gives 45 days. Maryland gives 45 days. Colorado gives about 38 days (May 1 to June 8).

The risk: if you don't open your mail for a week, you've already burned a quarter of Florida's window. Pro tip: photograph the postmark on the envelope as evidence of when the notice was mailed — this is your proof if there's a dispute about whether you filed on time.

Variable Deadlines (By County or Jurisdiction)

Some states don't have a single statewide deadline — it varies by county. California has two possible deadlines depending on your county (September 15 for 11 counties, November 30 for the other 47). Cook County, IL has different windows for each of its 38 townships. New York varies by municipality (most use the 4th Tuesday in May, but Westchester and other areas have different dates).

The risk: googling “[state] appeal deadline” gives you the wrong answer for your specific county. Always verify with your county assessor's office or check your state's appeal guide for county-level details.

Board Session Deadlines

You must file before the review board convenes — and meeting dates can shift year to year. Tennessee's County Board of Equalization meets around June. North Dakota's County BOE meets in the first 10 days of June. Wisconsin's Board of Review starts no earlier than the 4th Monday in April. The risk: board meeting dates are announced locally and can be hard to find online. Call your county assessor's office in advance and ask when the board will meet.

What Happens If You Miss the Deadline

Best case: You wait until next year and file then. One year of overpayment.

Worst case: You're locked in for the full reassessment cycle. In Cook County, IL, the triennial cycle means a missed deadline can cost you three years. In Maryland, the triennial group system means missing the first-year appeal window eliminates your leverage for the entire three-year period. In Pennsylvania, the 2026 tax year deadlines already passed in mid-2025 — the next filing window (for 2027 taxes) doesn't open until approximately August 2026.

Can you get an extension? Almost never. Courts treat appeal deadlines as jurisdictional, meaning they are a prerequisite to the board's authority to hear your case. Even one day late is one day too late. A small number of states allow late filings for clerical errors by the assessor (wrong address, wrong owner name) — but not for disagreements on value.

The real cost: Let's put numbers to it. The National Taxpayers Union Foundation estimates that 30–60% of properties are overassessed. If you're overassessed by $50,000 at a 2% tax rate, that's $1,000 per year. Miss one year, and that's $1,000 gone. Miss a three-year cycle, and it's $3,000. And in some states, a missed deadline doesn't just cost you money — it sets a higher baseline for future assessments.

The takeaway: if you're even slightly considering an appeal, file now. You can always withdraw later. You can never file late.

State-by-State Deep Dives: 10 Key States

These are the 10 highest-volume states for property tax appeals. Each has unique rules, forms, and filing quirks that go beyond the table above.

How to Prepare Before Your Deadline

Work backward from your deadline. Here's the timeline that gives you the best chance of a successful appeal:

For the full step-by-step process — including how to find comparable sales, what to say at your hearing, and how the appeal process works — see our complete guide to appealing your property taxes. And if you're 65 or older, check our senior exemptions guide — exemption application deadlines are often separate from appeal deadlines.

Frequently Asked Questions

The Bottom Line

Property tax appeal deadlines are the one part of the process where being right doesn't matter. You can have the strongest evidence, the clearest overassessment, and the most compelling comparable sales — and none of it matters if you file one day late.

The deadlines in this guide are current as of February 2026, but they can change. Always verify with your county assessor's office. And if you're not sure whether your assessment is worth appealing, start by entering your address below — we'll show you how your assessment compares to actual market data.

The only mistake worse than a bad assessment is a missed deadline. Once you know yours, use our step-by-step appeal checklist to prepare.