The window to file opens once assessment notices go out and closes on the date printed on that notice, so the practical first step is reading your own notice rather than assuming the deadline is the same every year.
A successful appeal lowers the assessed value the mill rate is applied to, which lowers the bill, but it has no effect on what a buyer would pay for the house, since assessed value for tax purposes and market value for a sale are calculated on entirely different bases.
Whether an appeal is worth filing depends on how your specific assessment, taxed on 80 percent of that assessed value, compares to genuinely similar sold properties in 2026, not on a general sense that taxes feel high.
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