ZIP Code 04421

04421 is one of Maine's ZIP codes, delivering to addresses in Castine, Hancock County.

City: Castine
County: Hancock County
State: Maine
Prefix: 044xx

Where this code sits

04421 is part of the 044xx range, the group of codes handled by one mail processing centre. Castine is served by 2 ZIP codes in total.

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 04421 delivers to without sharing its boundary.

207 Area code 207

ZIP codes nearest 04421

The ZIP codes whose reference points sit closest to 04421.
ZIP code	Distance	Delivers to
ZIP code 04420	0.3 mi	Castine, ME
ZIP code 04617	4.1 mi	Brooksville, ME
ZIP code 04476	5.3 mi	Penobscot, ME
ZIP code 04642	5.7 mi	Harborside, ME
ZIP code 04972	6.9 mi	Sandy Point, ME
ZIP code 04981	7.5 mi	Stockton Springs, ME
ZIP code 04974	8.4 mi	Searsport, ME
ZIP code 04673	8.8 mi	Sargentville, ME

Straight-line distance between place reference points, not driving distance. Where a place has no Census Gazetteer point, its postal centroid is used instead.

Each point is the reference point for 04421, plotted from its record coordinates.

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

Scope ZIP code 04421. Source GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated 15 July 2026. A ZIP code is a set of delivery routes, not an area; the point shown is a record coordinate, not a centre.