What Is Notice of Assessment?
An official document from the county assessor informing a property owner of their property's assessed value for the upcoming tax year.
Detailed Explanation
How It Varies by State
Mailed when value changes or a new exemption is applied. Includes property details, appraised value, and protest instructions. 30-day protest window.
Shows just value, assessed value, exemptions, and proposed taxes from all taxing authorities. 25-day appeal window.
Published by assessor. Grievance Day allows property owners to file formal challenges.
Mailed when township reassessment occurs. Cook County provides online lookup of assessment changes.
Common Misconceptions
Myth:If I did not receive a notice, my value did not change
Reality:Some states only mail notices when values change. Others publish the roll online. Check your county assessor's website annually even if you do not receive a physical notice.
Myth:The notice is the same as my tax bill
Reality:The notice shows the assessed value. The tax bill, which comes later, shows the actual amount you owe after all rates and exemptions are applied.
Myth:The property details on the notice must be accurate
Reality:Data errors are common. Always verify the square footage, lot size, bedroom/bathroom count, and property class listed on your notice against your actual property.
Impact on Your Tax Bill
If your notice shows 2,400 square feet but your home is actually 2,100 square feet, that 300 square feet of error could inflate your value by $30,000 to $60,000 depending on your market. In a state with 2% effective tax rate, that translates to $600 to $1,200 per year in excess taxes from a simple data error.
Related Articles
Understanding Your Property Assessment Notice: What Every Homeowner Should Know
Learn how to read your property assessment notice, what every section means, how it differs from your tax bill, and how to spot signs of overassessment before the appeal deadline.
Property Tax Appeal Deadlines by State: The Complete 2026 Calendar
Every state's property tax appeal deadline for 2026, including fixed dates, rolling deadlines, and what happens if you miss yours. Updated for the current tax year.
Related Terms
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