Property taxes are based on your home's assessed market value, but markets change. If home prices in your neighborhood have softened, slowed, or corrected since your last assessment, your current assessed value may no longer reflect what your property would realistically sell for today.

Assessments often assume properties are in average condition. However, factors like deferred maintenance, needed repairs, outdated kitchens or bathrooms, foundation issues, or roof age can materially impact market value.

County assessors determine value by analyzing 'comparable' properties: recent nearby sales used to estimate your home's value. However, small differences can significantly impact value: lot size, renovations, view, school district boundaries, upgrades, or even which side of a street a property sits on. If higher-end or non-comparable properties were used, your valuation may be inflated.

Assessment records are based on data, and data can contain mistakes.

Certain exemptions reduce your taxable value, but they are not always automatically applied.