Sussex County, Delaware

Sussex County population, land area and income

Sussex County had 271,134 residents in the Census Vintage 2024 estimate, on 936.1 square miles of land. It is the largest by land of Delaware's 3 county-equivalents. That works out to 289.6 people per square mile, 3.0 times the US average of 96.3, and in the top quarter nationally.

The median county-equivalent in Delaware has 271,134 residents, about the same as Sussex County.

Its SAIPE 2023 median household income of $78,092 is in the top quarter among 3,143 counties with an estimate.

How Sussex County's population changed since 2020

Sussex County gained 32,480 residents between the July 2020 and July 2024 estimates, a rise of 13.6%. That ranks 1st of 3 in Delaware for growth. The median Delaware county changed by +5.7%, and the state as a whole by +6.0%.

Since the April 2020 estimates base, Sussex County recorded 9,973 births and 14,225 deaths, a natural change of -4,252. Net international migration added +3,344 and net domestic migration, people moving to or from other US counties, came to +34,714. The largest single component was domestic migration, which added 34,714 people.

Where Sussex County is

The Census internal point of Sussex County is at 38.673200, -75.337000. It sits in UTM zone 18N. The map shades Delaware's 3 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Sussex County outlined. Dots are towns of 1,000+ people with residents in it.

Towns in Sussex County

16 incorporated places of 1,000+ people have residents in Sussex County, 63,225 people together, or 23% of the county. Each figure counts only the part of the town inside Sussex County; towns marked "part" extend into another county. The largest is Seaford with 8,952.

Counties bordering Sussex County

The Census 2024 county adjacency file lists 6 neighbors for Sussex County, including 5 across a state line. The most populous is Kent County, DE, with 192,690 residents. Distances run between Census internal points in a straight line.

• Kent County

  192,690 people

  31 mi NNW

• MD

  Wicomico County, MD

  106,329 people

  26 mi SW

• NJ

  Cape May County, NJ

  93,875 people

  39 mi NE

• MD

  Worcester County, MD

  54,337 people

  31 mi S

• MD

  Caroline County, MD

  34,248 people

  30 mi WNW

• MD

  Dorchester County, MD

  33,138 people

  42 mi WSW

Distance to Dover and the nearest big city

Dover is 34.8 miles NNW of Sussex County's internal point in a straight line. The nearest place of 100,000 or more is Baltimore, MD (population 568,271), 81.0 miles away. The nearest place of 10,000 or more is Milford, DE (population 14,079), 17.0 miles away.

Sussex County FIPS code

The FIPS code of Sussex County is 10005: state code 10 for Delaware plus county code 005. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $78,092.