Delaware County Map: All 3 Counties
Delaware has only 3 counties: New Castle, Kent, and Sussex. Established in 1682 under William Penn, Delaware’s tri-county structure is the smallest county roster of any state in the nation except Hawaii (if Kalawao is excluded) and Rhode Island.
Delaware at a Glance
Delaware County Map
Counties of Delaware with the state capital, Dover, marked. Hover a shape for its name or click it to jump to its row in the list below.
Printable Blank Map of Delaware with All Counties
Download the Delaware outline as SVG or PNG, or print it to PDF, in several variants: blank boundary, with counties lines, color-filled and labeled. Free to use (CC0).
The Twelve-Mile Arc: America’s Only Curved State Boundary
Delaware’s northern boundary with Pennsylvania is defined by the historic Twelve-Mile Arc surveyed around New Castle Courthouse.
In 1681, King Charles II granted Pennsylvania to William Penn, and in 1682, the Duke of York leased the "Three Lower Counties upon Delaware" (New Castle, Kent, Sussex) to Penn to provide his new colony with ocean access.
To establish the northern boundary, royal surveyors drew a circular arc with a 12-mile radius centered on the cupola of the New Castle Courthouse. This 1701 survey remains the only circular state border in the United States.
The three counties formally broke away from Pennsylvania in 1704 to form an independent colonial assembly, and on December 7, 1787, Delaware became the "First State" to ratify the United States Constitution.
While New Castle and Sussex counties modernized to elected County Councils, Kent County preserves the historic colonial title "Levy Court" for its 7-member legislative and administrative commission.
The Court of Chancery & Corporate Capital of America
Delaware’s unique judicial structure makes its three counties the legal home to over 65% of Fortune 500 corporations.
Established in 1792, the Delaware Court of Chancery is a specialized court of equity that resolves corporate governance, merger, and shareholder disputes without juries. Rather than being fragmented across three separate county court circuits, Chancery chancellors possess statewide jurisdiction.
Over 1.9 million legal business entities are registered in Delaware—predominantly through registered agents located in New Castle County (Wilmington)—exceeding the human population of the entire state (989,948).
Delaware levies zero state or county sales tax, making retail and commercial logistics in New Castle and Sussex counties a major regional economic draw for Maryland and Pennsylvania shoppers.
How Local Government Operates in Delaware: County Council / Levy Court & Court of Chancery
New Castle and Sussex counties are governed by County Councils, while Kent County retains the historic "Levy Court." Delaware’s renowned Court of Chancery holds statewide equity jurisdiction over global corporate governance without county jury trials.
Delaware County Rankings: Population & Land Area
Comparative demographic and territorial distribution across Delaware's largest administrative subdivisions based on the 2020 US Census Decennial count.
Top 10 Most Populous Counties
| # | County | Seat | Population | % State |
|---|---|---|---|---|
| 1 | New Castle County | Wilmington | 570,713 | 57.7% |
| 2 | Sussex County | Georgetown | 237,375 | 24.0% |
| 3 | Kent County | Dover | 181,858 | 18.4% |
Top 10 Largest Counties by Land Area
| # | County | Seat | Land Area | % State |
|---|---|---|---|---|
| 1 | Sussex County | Georgetown | 936.2 sq mi | 48.0% |
| 2 | Kent County | Dover | 586.1 sq mi | 30.1% |
| 3 | New Castle County | Wilmington | 426.3 sq mi | 21.9% |
Which county of Delaware are you in?
Use your device location to see which county of Delaware you are in right now.
List of All 3 Counties in Delaware
Every county in Delaware is listed below with its seat, 2020 Census population, land area and FIPS code. Search by name, seat or FIPS, sort any column, or export the full table as CSV.
County | Seat | 2020 Census Pop | Land Area (sq mi) | FIPS |
|---|---|---|---|---|
New Castle County | Wilmington | 570,713 | 426 sq mi | 10003 |
Sussex County | Georgetown | 237,375 | 936 sq mi | 10005 |
Kent County | Dover | 181,858 | 586 sq mi | 10001 |
Neighboring States Bordering Delaware
County maps, lists and printable blank maps for the states that border Delaware:
Data Sources & FIPS Codes
Delaware uses state FIPS code 10; each county adds a three-digit code to form the five-digit FIPS (now INCITS 31) identifiers in the table. Populations are 2020 Census counts and land areas come from the Census Gazetteer. The map above is drawn from the Census Bureau's generalized 2017 cartographic boundary file (1:10,000,000), so it suits overview and printing, not parcel-level or legal boundary questions; for those, check the local assessor or GIS office.
Questions About Delaware Counties
Why does Delaware have only 3 counties?
Delaware spans only 1,949 square miles (the second-smallest state after Rhode Island). The Three Lower Counties were established in 1682 under William Penn and satisfied all colonial settlement needs. Given its compact geography (only 96 miles long), three counties have proven sufficient for over 340 years.
What is a "Levy Court" in Delaware?
The Levy Court is the official name of the elected county commission in Kent County, Delaware. Historically, colonial county boards met to "levy" taxes for roads, jails, and poorhouses. While New Castle and Sussex renamed their bodies to County Council, Kent County retains the colonial name.
Which Delaware county has the lowest property taxes?
Sussex County traditionally maintains the lowest effective county property tax rates in Delaware, funded in part by significant real estate transfer taxes from coastal second-home purchases and beach tourism revenue.
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