Delaware Building Permits — Complete Guide (2026)
Find, Apply & Track Permits in Cities and Counties Across Delaware
Delaware is the second smallest state with a simple, accessible permitting system. New Castle County (Wilmington) handles the bulk of permit volume. Sussex County on the shore sees significant vacation home construction activity.
How building permits work in Delaware
Building permit requirements and processing times in Delaware vary by city and county. Use the links below to apply, check status, schedule inspections and find permit information for your location.
Learn the step-by-step permit process →Not sure where to apply?
Enter your city or address to find your permit office.
Permit costs by type — Delaware
| Permit Type | Fee Range | Processing Time | Notes |
|---|---|---|---|
| Electrical | $75–$200 | 1–3 days | Licensed electrician required |
| Plumbing | $70–$185 | 1–3 days | Licensed plumber required |
| HVAC / Mechanical | $80–$220 | 1–4 days | Oil heat common — conversion permits common |
| Roofing | $100–$275 | 1–3 days | Full replacement permit required |
| New Construction | $600–$1,800 | 2–6 weeks | Sussex County coastal homes see premium costs |
| Room Addition | $350–$900 | 2–5 weeks | Straightforward process in most areas |
| Deck / Patio | $125–$375 | 1–3 weeks | Coastal setback rules may apply in Sussex |
| Pool | $175–$500 | 2–4 weeks | High demand in Sussex County |
| Solar | $80–$220 | 1–4 days | Good state net metering policy |
| Fence | $55–$150 | 1–5 days | Coastal setback requirements near dunes |
Major Delaware cities — apply online
Most Delaware building permits are issued by cities. Click your city to access the permit portal, apply online, or check permit status.
Permit costs by county — top Delaware counties
County building departments handle unincorporated areas. Click a county to access its permit portal directly.
How to get a building permit in Delaware
Identify your county system
New Castle County has a robust online permitting portal. Kent County (Dover) and Sussex County (Georgetown) have their own separate systems.
Submit permit application
New Castle County accepts online submissions for most project types. Kent and Sussex are mostly paper-based.
Plans if required
Structural work requires stamped plans. Sussex County coastal projects may need flood elevation certificates.
Inspections
New Castle County has a dedicated inspection division. Sussex County may have longer waits during busy beach-home construction seasons.
Certificate of Occupancy
Required for new construction and major additions.
ADU permits in Delaware — what you need to know
🏠 Delaware ADU-friendly status: Limited
Delaware has no statewide ADU mandate. Wilmington and Newark allow accessory apartments with conditional use permits. New Castle County updated zoning in 2022 to allow ADUs in most residential zones.
Find a licensed Delaware contractor
Delaware requires licensed professionals for most permitted work. Always verify a contractor's license before hiring — it protects you and is required for most permit types.
General Contractors
Find pre-screened general contractors for your Delaware home project. Compare quotes on permitted work.
Find a Contractor →Verify DE License
Verify your contractor holds a valid Delaware Division of Professional Regulation license before any permitted work begins.
Verify DE License →Electricians & Plumbers
Specialty-licensed electricians and plumbers are required for all permitted electrical and plumbing work in Delaware.
Learn More →Ready to get started? Browse verified, licensed contractors serving Delaware homeowners and get free quotes on your project.
🔍 Find a Contractor Near YouFrequently asked questions — Delaware permits
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