Delaware Property Tax Appeal Guide
How to challenge your property tax assessment in Delaware - deadlines, process, and a savings calculator.
What This Data Tells Us About Appeals in Delaware
- Administrative filing in Delaware is listed at $0, so the first barrier is evidence and timing, not a petition fee.
- This ACS extract does not store how often Delaware assessments are reduced on appeal; comparable sales and property-record errors are the evidence the named board typically asks for.
- The typical window centers on March; confirm the current county notice date before relying on the statewide summary. Deadline shape differs on Kansas and Ohio.
Primary signal
The administrative filing is usually free
File with the County Board of Assessment Review. The reported filing-fee structure is $0; later court or tribunal stages may use a different schedule.
Decision signal 2
Delaware's process has its own procedural details
Delaware has three counties (New Castle, Kent, Sussex) with different assessment schedules. New Castle County had a major reassessment in 2023.
Decision signal 3
The filing window centers on March
Within 30 days of the assessment notice. Deadlines can vary by county and assessment cycle, so confirm the current date with the local assessor before relying on this guide.
Decision signal 4
This extract does not store an appeal-win rate
The ACS county medians on this site do not include how often Delaware assessments are reduced on appeal. Recent comparable sales and documented property-record errors are the evidence boards typically ask for.
How to read this guide and disclaimer
Use the ranked signals above as a preparation order, not as a forecast. Start with the filing window and named appeal body because a strong valuation argument cannot cure a missed deadline or a filing sent to the wrong office. Then compare the assessment with recent, genuinely similar properties and document factual errors such as incorrect square footage, condition, or classification.
An estimated success rate is not part of this ACS extract. Keep copies of the assessment notice, evidence, forms, delivery confirmation, and every response from the taxing authority. If a state rule and a county instruction differ, follow the current instruction issued by the office that will hear the appeal.
This guide is for informational purposes only and is not legal or tax advice. Deadlines, filing fees, and procedures vary by county within Delaware and can change year to year. Always verify the current rules with your local assessor's office, or a licensed attorney or tax professional, before filing. Source: Delaware Division of Revenue.
Appeal calendars beside Delaware
Other state boards, not geography. Use them to see whether Delaware's March window is unusual; start with Kansas and Ohio.
| Peer state | Typical month | Filing fee |
|---|---|---|
| Kansas Also open Kansas appeal steps | March | $0 |
| Ohio Also open Ohio appeal steps | March | $0 |
| South Dakota Also open South Dakota appeal steps | March | $0 |
| Arizona Also open Arizona appeal steps | April | $0 |
| Connecticut Also open Connecticut appeal steps | February | $0 |
Appeal Deadline
Within 30 days of the assessment notice
Appeal Body: County Board of Assessment Review
Step-by-Step Appeal Process
- 1
Review your assessment from the county Board of Assessment
- 2
File a written appeal with the county Board of Assessment Review
- 3
Attend a hearing and present comparable sales or an independent appraisal
- 4
If denied, appeal to the Superior Court of Delaware
Delaware-Specific Notes
Delaware has three counties (New Castle, Kent, Sussex) with different assessment schedules. New Castle County had a major reassessment in 2023.
Source: Delaware Division of Revenue
Estimate appeal savings
After you have Delaware's deadline (March) and filing route (County Board of Assessment Review), project annual savings if an assessment cut sticks. The shared estimator lives on one tools URL so each state page keeps its own process facts instead of reprinting the same form.
Open appeal savings estimator →