Nantucket County ZIP Codes

Nantucket County is a county of Massachusetts.

ZIP codes: 3
Cities & towns: 2
Area codes: 2
Land area: 46.2 sq mi

Every ZIP code in Nantucket County

025xx

The complete list of Nantucket County, MA ZIP codes with the city each one delivers to.
ZIP code	City
02554	Nantucket
02564	Siasconset
02584	Nantucket

We do not publish a delivery type (standard, PO box, unique) or a neighbourhood for each ZIP.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 Nantucket County codes above are listed without a column we would have to invent.

Area codes covering Nantucket County

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

Where Nantucket County's ZIP codes sit

Each point is the reference point of one Nantucket 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 Nantucket 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.