Delaware counties

Every county in Delaware, with the ZIP codes recorded in each. Pick one to see its full ZIP code list.

counties: 3
ZIP codes: 96

All Delaware counties

Every Delaware county with the number of ZIP codes it holds and the city holding the most of them.
County	ZIP codes	Largest city
Kent County	21	Dover
New Castle County	52	Wilmington
Sussex County	23	Bethany Beach

Scope every county-equivalent recorded in Delaware. Source Census 2024 county Gazetteer (2024 Gazetteer) and GeoNames US postal codes (2026-07 postal dump). Updated 15 July 2026. Names and boundaries follow the Census Bureau's current county-equivalent set, not the DE postal source's older names.