Delaware Counties
Complete list of all 3 counties in Delaware with population, area, median income, and county seats — plus a free printable blank map.
Labeled outline map of Delaware counties. Download a printable version in SVG, PNG, or PDF.
All 3 Delaware counties
| County | County Seat | Population ▼ | Area | Median Income | Cities |
|---|---|---|---|---|---|
| New Castle | — | 573,431 | 426 mi² | $95,647 | 17 |
| Sussex | — | 267,041 | 936 mi² | $80,132 | 23 |
| Kent | — | 181,133 | 586 mi² | $76,597 | 17 |
How many counties does Delaware have?
Delaware has 3 counties covering 1,948 square miles and roughly 1,021,605 residents. The state was admitted to the Union in 1787 as the 1st state, and the current county boundaries reflect more than a century of administrative subdivision.
The largest county by land area is Sussex County at 936 square miles, home to about 267,041 residents. The most populous is New Castle County with approximately 573,431 residents — a density of about 1,346 people per square mile.
At the other end of the scale, Kent County has only about 181,133 residents.
Delaware’s capital is Dover, while the largest city is Wilmington — a common pattern in the United States, where many states placed their capitals in smaller, more central towns rather than their largest commercial hubs.
Related resources
Download a printable outline of Delaware’s county boundaries from our blank map of Delaware page — available in SVG, PNG, and PDF.
Use the What County Am I In? tool to detect which Delaware county a GPS location or address falls in, or the Address to County Lookup for batch input.
For demographic radius analysis, the Find ZIP Codes in Radius and Population Within Radius tools let you draw a circle around any Delaware address and see every ZIP code and the total population inside.
Two SimpleMapLab studies cover Delaware specifically: the 100-mile radius around Dover measures how much of the state lives within 100 miles of its capitol, and the loneliest town in Delaware ranks the state’s most isolated inhabited place. The county-counts blog post puts Delaware’s 3 counties in national context.
Frequently asked questions
Population and demographics are aggregated from ZIP-code-level US Census data via the SimpleMaps dataset. Countiesboundaries are from the US Atlas TopoJSON build of the Census Bureau’s TIGER/Line shapefiles. Land area is from the Census Gazetteer. State counts follow the US Census Bureau’s definition of counties and county-equivalents (50 states + DC = 3,143). All sources are public domain.