DE · 2026 appeal calendar

Delaware Property Tax Appeal Deadlines 2026.

Delaware property tax appeal deadlines and filing windows for commercial real estate. Verify with your local assessor or appeal board for the specific jurisdiction before filing.

Updated May 2026

Verify before filing. Statutory deadlines change, and many counties operate on their own schedule inside the state framework. Always confirm the current year's window with the assessor or appeal board for the specific jurisdiction before relying on a date.

2026 appeal calendar

Delaware deadlines at a glance.

State-level deadlines plus major sub-jurisdictions where the schedule diverges from the state default. Where a column says "Varies," confirm the date with the local assessor.

Month Type Event Date Details
January RP
Value Notices
1-Jan Assessment increase notices (Notice of Change) mailed by Jan 1
March RP
Appeal Deadline
15-Mar Kent County - Jan 31 New Castle Count - Mar 15 Sussex County - Mar 1

RP = Real Property · BPP = Business Personal Property · Both = Applies to both

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