ZIP Code 19721

19721 is one of Delaware's ZIP codes, delivering to addresses in New Castle, New Castle County.

City: New Castle
County: New Castle County
State: Delaware
Prefix: 197xx

Where this code sits

19721 is part of the 197xx range, the group of codes handled by one mail processing centre. New Castle is served by 3 ZIP codes in total; the full list, with the county each falls in, is on the New Castle page.

New Castle Delaware ZIP codes →

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 19721 delivers to without sharing its boundary.

302 Area code 302

ZIP codes nearest 19721

The ZIP codes whose reference points sit closest to 19721.
ZIP code	Distance	Delivers to
ZIP code 19712	0.0 mi	Newark, DE
ZIP code 19714	0.0 mi	Newark, DE
ZIP code 19715	0.0 mi	Newark, DE
ZIP code 19718	0.0 mi	Newark, DE
ZIP code 19725	0.0 mi	Newark, DE
ZIP code 19850	0.0 mi	Wilmington, DE
ZIP code 19880	0.0 mi	Wilmington, DE
ZIP code 19890	0.0 mi	Wilmington, DE

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 19721, plotted from its record coordinates.

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

Scope ZIP code 19721. 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.