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County ZIP codes · Delaware · FIPS 10003

New Castle County, DE ZIP Codes

New Castle County, Delaware has 54 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026): 31 residential and 23 for PO boxes or a single organization. 29 of the residential ones lie mainly in New Castle County and 2 mainly in a neighboring county; 2 cross the county line. Median household income ranges from $52,810 in 19801 (Wilmington) to $172,696 in 19707 (Hockessin) (Census Bureau, ACS 2020-2024).

  • ACS2020-24
  • Census2020

Where are the ZIP codes of New Castle County?

19701 · Bear: $111k19702 · Newark: $92k19703 · Claymont: $77k19706 · Delaware City: $84k19707 · Hockessin: $173k19709 · Middletown: $133k19710 · Montchanin: –19711 · Newark: $95k19713 · Newark: $77k19716 · Newark: –19717 · Newark: –19720 · New Castle: $75k19730 · Odessa: $112k19731 · Port Penn: $71k19732 · Rockland: $236k19733 · Saint Georges: $83k19734 · Townsend: $128k19735 · Winterthur: –19736 · Yorklyn: –19801 · Wilmington: $53k19802 · Wilmington: $54k19803 · Wilmington: $135k19804 · Wilmington: $80k19805 · Wilmington: $60k19806 · Wilmington: $89k19807 · Wilmington: $153k19808 · Wilmington: $94k19809 · Wilmington: $81k19810 · Wilmington: $113k19938 · Clayton: $100k19977 · Smyrna: $77k197341997719709197021972019938197111971319807198081980319707198091980419810198011980519701 · Bear: $111k19702 · Newark: $92k19703 · Claymont: $77k19706 · Delaware City: $84k19707 · Hockessin: $173k19709 · Middletown: $133k19710 · Montchanin: –19711 · Newark: $95k19713 · Newark: $77k19716 · Newark: –19717 · Newark: –19720 · New Castle: $75k19730 · Odessa: $112k19731 · Port Penn: $71k19732 · Rockland: $236k19733 · Saint Georges: $83k19734 · Townsend: $128k19735 · Winterthur: –19736 · Yorklyn: –19801 · Wilmington: $53k19802 · Wilmington: $54k19803 · Wilmington: $135k19804 · Wilmington: $80k19805 · Wilmington: $60k19806 · Wilmington: $89k19807 · Wilmington: $153k19808 · Wilmington: $94k19809 · Wilmington: $81k19810 · Wilmington: $113k19938 · Clayton: $100k19977 · Smyrna: $77k197341997719709197021972019938197111971319807198081980319701 · Bear: $111k19702 · Newark: $92k19703 · Claymont: $77k19706 · Delaware City: $84k19707 · Hockessin: $173k19709 · Middletown: $133k19710 · Montchanin: –19711 · Newark: $95k19713 · Newark: $77k19716 · Newark: –19717 · Newark: –19720 · New Castle: $75k19730 · Odessa: $112k19731 · Port Penn: $71k19732 · Rockland: $236k19733 · Saint Georges: $83k19734 · Townsend: $128k19735 · Winterthur: –19736 · Yorklyn: –19801 · Wilmington: $53k19802 · Wilmington: $54k19803 · Wilmington: $135k19804 · Wilmington: $80k19805 · Wilmington: $60k19806 · Wilmington: $89k19807 · Wilmington: $153k19808 · Wilmington: $94k19809 · Wilmington: $81k19810 · Wilmington: $113k19938 · Clayton: $100k19977 · Smyrna: $77k197341997719709197021972019938197111971319804
The residential ZIP codes of New Castle County (whole outlines, including the parts in neighboring counties), shaded by median household income in national fifths (ACS 2020-2024). <$54.1k$98.1k+no figure

Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries; ACS 2020-2024 5-year estimates (B19013).

How different are its ZIP codes?

The middle half of its ranked ZIP codes (1,000+ people living in households) report median household incomes between $76,826 and $111,198.

They carry 18 postal town names.

Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B19013).

All 31 residential ZIP codes in New Castle County

29 ZIP codes lie mainly in New Castle County; 2 more reach into it from a neighboring county and follow the first table.

Residential ZIP codes mainly in New Castle County, largest first; "In this county" is the share of the ZIP's land in the county
In this county
19720 New Castle 62,392 1,629 $75k $265k 100%
19702 Newark 55,683 1,982 $92k $346k 100%
19709 Middletown 53,234 686 $133k $471k 100%
19711 Newark 49,432 1,804 $95k $399k 100%
19701 Bear 42,984 1,618 $111k $373k 100%
19805 Wilmington 41,402 7,503 $60k $237k 100%
19808 Wilmington 39,082 2,842 $94k $338k 100%
19713 Newark 30,747 2,365 $77k $293k 100%
19810 Wilmington 26,530 3,360 $113k $441k 100%
19802 Wilmington 26,051 7,477 $54k $195k 100%
19803 Wilmington 22,279 1,760 $135k $457k 100%
19804 Wilmington 18,779 2,617 $80k $264k 100%
19707 Hockessin 17,376 1,318 $173k $557k 100%
19801 Wilmington 16,327 3,713 $53k $200k 100%
19703 Claymont 15,460 3,893 $77k $285k 100%
19809 Wilmington 14,311 2,118 $81k $315k 100%
19734 Townsend 14,214 178 $128k $431k 100%
19806 Wilmington 9,777 5,734 $89k $386k 100%
19807 Wilmington 7,815 430 $153k $937k 100%
19717 Newark 6,036 23,395 – – 100%
19706 Delaware City 2,038 805 $84k $263k 100%
19731 Port Penn 655 259 $71k $369k 100%
19730 Odessa 425 630 $112k $323k 100%
19733 Saint Georges 186 1,691 $83k $305k 100%
19736 Yorklyn 127 841 – – 100%
19732 Rockland 89 51 $236k $581k 100%
19710 Montchanin no residents 0 – – 100%
19716 Newark no residents 0 – – 100%
19735 Winterthur no residents 0 – – 100%

Partly in New Castle County

Residential ZIP codes mainly in another county that reach at least 1% into New Castle County, by their share here
In this county
19977 Smyrna 27,704 333 $77k $341k 22%
19938 Clayton 9,561 198 $100k $381k 15%

Download the 54 ZIP codes as CSV

Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates; county shares by land area (Census 2020 ZCTA-county relationship file).

Which ZIP codes cross the county line?

2 ZIP codes of New Castle County extend into another county. A ZIP code follows mail routes, not county borders.

Share of each ZIP code's land in New Castle County and in the neighboring counties
ZIPIn New CastleElsewhere
1997722%Kent County 78%
1993815%Kent County 85%

Source: U.S. Census Bureau, 2020 ZCTA-county relationship file (shares of land area).

PO Box and single-organization ZIP codes

ZIP codes in New Castle County without a residential area (GeoNames postal codes)
ZIPPostal name
19708Kirkwood
19712Newark
19714Newark
19715Newark
19718Newark
19721New Castle
19725Newark
19726New Castle
19850Wilmington
19880Wilmington
19884Wilmington
19885Wilmington
19886Wilmington
19890Wilmington
19891Wilmington
19892Wilmington
19893Wilmington
19894Wilmington
19895Wilmington
19896Wilmington
19897Wilmington
19898Wilmington
19899Wilmington

Source: GeoNames postal codes (CC BY 4.0).

Which first three digits do New Castle County's ZIP codes use?

The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. New Castle County's ZIP codes use 3 prefixes: 197, 198 and 199.

Three-digit prefixes of New Castle County's ZIP codes, the sectional center for each (USPS labeling list L005, effective October 1, 2026) and how many of the prefix's codes are New Castle County's
PrefixSectional centerHereAll codes
197 Wilmington, DE (SCF 197) 27 27
198 Wilmington, DE (SCF 197) 25 25
199 Wilmington, DE (SCF 197) 2 44

Source: U.S. Postal Service, labeling list L005 (3-digit ZIP Code prefix groups, SCF sortation), effective October 1, 2026.