New Castle County, Delaware Tax Assessors' Office

Where is the New Castle County Tax Assessor's Office?

While many counties have county-wide tax assessors, New Castle County has one cities and towns with their own local tax assessors. If your property is located within any of these localities, see that page for your tax assessor's contact information.

What can the New Castle County Assessor's Office do for me?

The New Castle County Tax Assessor's Office oversees the appraisal and assessment of properties as well as the billing and collection of property taxes for all taxable real estate located in New Castle County.

Contact the assessor's office if you need help with paying your property taxes, applying for a homestead exemption or other tax exemption, reporting upgrades to your home, appealing your property tax assessment, or verifying your property records.

Submitting a New Castle County property tax appeal

If you believe that your house has been unfairly overappraised (i.e. appraised at a value higher than the true market value of the property), you can attempt to get your home re-appraised at a lower value by contacting the Assessor's Office to submit a property tax appeal.

You will have to submit a form describing your property and sufficient proof that it is overassessed, including valuations of similar homes nearby as evidence. If your appeal is accepted, your home assessment (and property taxes) will be lowered as a result.

If you would like to appeal your property, call the New Castle County Assessor's Office at (302) 395 5520 and ask for a property tax appeal form. Keep in mind that property tax appeals are generally only accepted in a 1-3 month window each year.

For more information and example appeals, see how to appeal your property taxes.

How can I contact New Castle County?

You can try contacting the New Castle County local government directly with any issues the Assessor's Office can't solve. In many counties, certain property records such as deeds are kept in the county courthouse or county archives instead of at the tax assessors' office.

The county seat for New Castle County is located in the Louis L. Redding City/County Building in Wilmington, which is located at 800 North French Street. You can direct your general inquiries to New Castle County with the contact info listed below.

New Castle County Phone Number

302-395-8383

New Castle County Fax Number

302-395-8385

New Castle County Louis L. Redding City/County Building Address

Louis L. Redding City/County Building
800 North French Street
Wilmington, DE 19801-3590

Useful New Castle County Links:

• New Castle County Assessors' Office Homepage
• City of Wilmington - Property Tax Search
• New Castle County Search by Parcel ID, address, or owner name
• New Castle County Government Homepage
• Property Tax Search Tool