Delaware ADU Laws

Complete 2026 guide to accessory dwelling unit regulations

○Local Control Only

📋Quick Facts

Owner Occupancy
May be required
Parking
Set locally
Approval Process
Varies locally

📜Recent Legislation

SB23 (2024) - Proposed requiring local governments to permit ADU construction, but bill was substituted/died when legislature ended

⚠️Key Requirements & Restrictions

  • •No statewide ADU law - entirely local control
  • •SB23 would have required local governments to permit ADUs without prohibitive barriers
  • •Counties typically require minimum 200-400 square feet for ADUs
  • •Wilmington and other municipalities have their own varying regulations
  • •Most offer internal, detached, and conversion ADU options locally

📖Detailed Analysis

No statewide ADU law - entirely local control. SB23 (2024) would have required local governments to permit ADU construction without prohibitive barriers, but the bill was substituted/lieu in May 2024 and died when the General Assembly ended. The act was intended to expand affordable housing opportunities by requiring ADU permits in all jurisdictions. Currently varies by municipality - counties typically require minimum 200-400 square feet, and local jurisdictions like Wilmington have their own regulations. Delaware represents failed attempt at statewide ADU mandate, returning to traditional local control model.

🔗Official Resources

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⚠️ Disclaimer

The information provided on this website is for general informational purposes only and does not constitute legal, financial, or professional advice. ADU laws, regulations, and requirements vary by jurisdiction and change frequently. While we strive to keep this information accurate and up-to-date, we make no representations or warranties of any kind about the completeness, accuracy, reliability, or suitability of this information. Always consult with qualified local professionals, including attorneys, architects, and your local planning department, before making any decisions regarding ADU construction or investment. Use of this information is at your own risk.

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Last updated: February 2026