Delaware County ZIP Codes

Delaware County is a county of Iowa.

ZIP codes: 10
Cities & towns: 10
Area codes: 1
Land area: 578 sq mi

Every ZIP code in Delaware County

506xx–523xx

The complete list of Delaware County, IA ZIP codes with the city each one delivers to.
ZIP code	City
50654	Masonville
52035	Colesburg
52036	Delaware
52038	Dundee
52041	Earlville
52050	Greeley
52057	Manchester
52223	Delhi
52237	Hopkinton
52330	Ryan

We do not publish a delivery type (standard, PO box, unique) or a neighbourhood for each ZIP. USPS delivery-type products are licensed, and no clean-rights source maps ZIP codes to neighbourhoods — so the Delaware County codes above are listed without a column we would have to invent.

Cities and towns in Delaware County

Area codes covering Delaware County

Telephone and postal boundaries are drawn by different bodies, so these codes overlap the county without matching its edges.

563 Area code 563

Where Delaware County's ZIP codes sit

Each point is the reference point of one Delaware County ZIP code, plotted from its record coordinates. The outline is the convex envelope of those points — a footprint, not a boundary.

Reference points and footprint
Not an official NANPA boundary
Not a USPS delivery area

Scope every ZIP code recorded in Delaware County. Source GeoNames US postal codes (2026-07 postal dump), Census 2024 county Gazetteer (2024 Gazetteer) and geoinfo-dataset (full_dataset) ZIP→NPA (2018 snapshot). Updated 16 July 2026. The outline is a convex envelope of ZIP reference points, not a jurisdiction boundary.