A Certificate of Error (COE) corrects a verified factual mistake in your assessment—e.g., wrong square footage, misclassification, a non-existent or demolished building, or wrong unit count. It's often used after appeal deadlines pass, can apply to the current year and up to three prior years, and may produce a refund. Apply through the Assessor or Board of Review with supporting documentation.
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What is a Certificate of Error and how can I apply?
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