Delaware Counties by Population (2024)

Population

200K

250K

300K

350K

400K

450K

500K

550K

Hover/click a county for data.
County
2024 Pop.
Change (2020)
Area (mi²)
Density (/mi²)
Location
New Castle County581,9301.93%1641,366New Castle County location
Sussex County270,57113.39%361289Sussex County location
Kent County191,8205.21%226327Kent County location
  1. Delaware Census State Data Center
  2. US Census State Population Estimates - Most recent state estimates from the Census Bureau's Population Estimates Program
  3. US Census County Population Estimates - Most recent county estimates from the Census Bureau's Population Estimates Program
  4. American Community Survey (2009 - 2013)
  5. Census QuickFacts
  6. Historical Populations of States and Counties (1790 - 1990)

Sources