Delaware Property Tax Appeal Guide
Delaware's three counties recently completed reassessments to current fair market value, replacing decades-old base-year values.
100%
Statutory percentage
Varies by county (typically March 1 – April 30)
Verified July 2026 — confirm on your notice
Del. Code tit. 9 (county boards of assessment review)
Governing state code
How to File in Delaware
Review your county assessment notice following the recent statewide reassessment.
Request an informal review with the county assessment office.
File a formal appeal with the county Board of Assessment Review by the stated deadline.
Present comparable sales or an independent appraisal at the hearing.
Appeal to the Superior Court if the Board denies relief.
Deadlines and ratios vary by county and change over time — always confirm with your local assessor. This is general information, not legal advice.
Are you actually over-assessed in Delaware?
Check this property against recent comparable sales for $4.99. If the evidence says you have no case, you know that before you spend a filing deadline on it — and if it does, the same $4.99 is credited toward the full appeal packet.
A worked example in Delaware
Say the assessor values your home at $400,000, but comparable sales show it is really worth $350,000 — a $50,000 over-assessment. Delaware taxes the full market value, so the taxable amount drops by the same amount. At a typical effective rate of ~1.5%, that is about $750 back in your pocket every year until the value is corrected.
Illustration only. Your actual rate, exemptions, and savings depend on your county and taxing districts — run your own numbers.
Common grounds for a Delaware appeal
Over-market valuation. Comparable sales of similar nearby homes closed below the value the assessor placed on yours.
Errors in the property record. The county has the wrong square footage, bedroom or bathroom count, lot size, or condition on file.
Unequal (non-uniform) assessment. Comparable properties in your area are assessed for less than yours, regardless of market value.
Physical or external problems. Deferred maintenance, functional issues, or an external nuisance depress what a buyer would pay.
Overvaluation · Unequal assessment · Incorrect classification
Don’t overlook exemptions
An appeal lowers your value, but exemptions cut your taxable base directly — and both stack. Most owners qualify for a homestead exemption on their primary residence, and many states add relief for owners over 65, veterans, and people with disabilities. Confirm you are enrolled with your Delaware county assessor before filing — it is the fastest saving most people miss.
- Senior School Tax Credit Up to $500 credit
- Age 65+, Delaware resident
- Disabled Veteran Exemption Varies by county
- 100% service-connected disability
Who hears a Delaware appeal
Your appeal is decided by County Board of Assessment Review — the value itself is set by the County Assessment Office, which is who you are disagreeing with.
- 1
Board of Assessment Review
- 2
Superior Court
Each stage has its own deadline. Missing the first one usually closes the later ones for that tax year.
Key Delaware statutes
The sections a Delaware appeal is argued under. Quote one exactly as written — a paraphrased or renumbered citation is worse than none.
- 9 Del.C. §8306
- Assessment of Real Property
- 9 Del.C. §8312
- Board of Assessment Review
- 9 Del.C. §8337
- Senior School Tax Credit
- 9 Del.C. §8355
- Appeal to Superior Court
Official Delaware resources
These are state government sites. The form and portal you actually file through are published by your county assessor.
Delaware property tax appeal questions
- When is the deadline to appeal property taxes in Delaware?
- Varies by county (typically March 1 – April 30). Verified July 2026. Deadlines vary by county and change from year to year, so always confirm the date printed on your own assessment notice before you file.
- Who decides a property tax appeal in Delaware?
- County Board of Assessment Review hears it. The full path is: Board of Assessment Review, then Superior Court.
- What is the assessment ratio in Delaware?
- Varies by county (60%–100% of market value). That is the share of value your bill is calculated on, so lowering the assessed value lowers the bill proportionally.
- What grounds can I appeal on in Delaware?
- Delaware recognises these grounds: Overvaluation, Unequal assessment, Incorrect classification. Overvaluation is the most common — you show comparable sales that closed below your assessed value.
- What property tax exemptions does Delaware offer?
- Senior School Tax Credit — Up to $500 credit, for age 65+, Delaware resident; Disabled Veteran Exemption — Varies by county, for 100% service-connected disability. Exemptions reduce your taxable base directly and stack with an appeal, so check both.
- What is the average property tax rate in Delaware?
- About 0.54% of market value per year statewide. Your own rate depends on your county and its taxing districts, so treat this as a benchmark rather than your bill.
Delaware Tax Estimator
$0 / yr
Based on 100% ratio & avg. millage. Estimate only.
Generate your Delaware appeal packet
Check your property for $4.99 (credited), then get the full comparable-sales packet and AI appeal letter for a flat $29 — $19 at launch.