Property Tax Reassessments: What Triggers Them and How to Appeal

A property tax bill that suddenly jumps is almost always the result of a reassessment — a local government’s updated estimate of your home’s value, used to calculate what you owe. Reassessments aren’t random; they’re typically triggered by specific events, and understanding them makes an unexpected increase far less confusing.

Common reassessment triggers:

• A sale or transfer of the property, which in many states resets the assessed value to the purchase price
• Major renovations or additions, such as a new bedroom, bathroom, or square footage increase
• Scheduled cyclical reassessments, which many counties conduct every one to five years regardless of any changes
• Broad market-wide adjustments, when a jurisdiction updates values across an area to reflect rising home prices

If a new assessment looks too high, most jurisdictions allow an appeal, typically through these steps:

• Review the assessment notice for the assumptions used, including square footage and condition
• Pull comparable sales for similar homes in your area during the same assessment period
• File a formal appeal within the jurisdiction’s deadline, which is often 30 to 60 days from the notice date
• Attend a hearing or submit evidence if the informal review doesn’t resolve the discrepancy

Reassessments feel arbitrary, but they almost always trace back to a specific trigger — and a successful appeal, when the assessment is genuinely off, can meaningfully lower your monthly escrow payment going forward. It’s worth the hour it takes to check the numbers before assuming the bill is correct.