The Office of Assessment oversees the process of assessing property, reviewing applications for assessment exemptions, and maintaining tax parcel and map information. Members of our staff are available to assist you from 8 a.m. to 4 p.m., Monday through Friday.

Assessment Process & Applicability

New Castle County property assessments are based upon 1983 property values. When a certificate of occupancy is issued after a building is constructed or improved, an assessor visits the property to determine the new assessment rate. The property assessment determines the amount of your property tax bill, as well as your school district's tax bill.

Appealing an Assessment

Those whose property is reassessed and who believe the new assessment is in error may appeal the assessment. New Castle County's Board of Assessment Review hears and makes ruling on these appeals.