ZIP Code 21661

21661 is one of Maryland's ZIP codes, delivering to addresses in Rock Hall, Kent County.

City: Rock Hall
County: Kent County
State: Maryland
Prefix: 216xx

Where this code sits

21661 is part of the 216xx range, the group of codes handled by one mail processing centre. It is the only ZIP code delivering to Rock Hall.

Rock Hall Maryland ZIP codes →

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 21661 delivers to without sharing its boundary.

ZIP codes nearest 21661

The ZIP codes whose reference points sit closest to 21661.
ZIP code	Distance	Delivers to
ZIP code 21620	9.7 mi	Chestertown, MD
ZIP code 21656	10 mi	Price, MD
ZIP code 21690	10 mi	Chestertown, MD
ZIP code 21658	10 mi	Queenstown, MD
ZIP code 21617	11 mi	Centreville, MD
ZIP code 21056	12 mi	Gibson Island, MD
ZIP code 21619	13 mi	Chester, MD
ZIP code 21052	13 mi	Fort Howard, MD

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 21661, plotted from its record coordinates.

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

Scope ZIP code 21661. 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.