Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — CITY/MD/ILCHESTER

Ilchester ZIP codes, Maryland

No ZIP code is named for Ilchester, MD; addresses there use a neighbouring town's name. 2 ZIP codes cover it: 21043 and 21075. Its area codes are 410, 443 and 667.

USPS city name
0 ZIP codes
Overlapping the city
2 more
Population
28,364
Area codes
410, 443, 667

NANPA lists no telephone rate centre for Ilchester itself, so these are the area codes of the nearest one, Ellicott City (0.0 miles). A town on an area-code boundary can differ from its neighbour.

Ilchester in numbers

About 28,364 people live in Ilchester, in 10,028 households, the 48th-largest of Maryland's 527 census places. The median household income is $152,103 a year, 47% above the Maryland median of $103,678 (US: $80,734). The median owner-occupied home is valued at $532,400 (27% above the Maryland median), and median gross rent is $2,115 a month. The median age is 36.8; 62.9% of adults 25 and over hold a bachelor's degree or higher (43.4% across Maryland); the average commute takes 28 minutes.

Population28,364Ilchester28,364
Households10,028Ilchester10,028
Median age36.8Ilchester36.8Maryland39.4US 38.9
Median household income$152,103Ilchester$152,103Maryland$103,678US $80,734
Median home value$532,400Ilchester$532,400Maryland$419,900US $332,700
Median gross rent$2,115Ilchester$2,115Maryland$1,705US $1,413
Bachelor's degree or higher62.9%Ilchester62.9%Maryland43.4%US 35.7%
Mean commute27.6 minIlchester27.6 minMaryland31.1 minUS 26.4 min
Population density2,637 / sq miIlchester2,637 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, for the census place Ilchester CDP. Survey estimates carry margins of error, wider for small places. Sources and methods.

ZIP codes covering Ilchester

These ZIP codes cover part of Ilchester but are addressed as somewhere else.

ZIP codes overlapping Ilchester
ZIP City Type Population Median income Median home
21043 Ellicott City , MD Standard 48,525 $148,125 $620,900
21075 Elkridge , MD Standard 37,363 $135,303 $455,300

Map of Ilchester ZIP codes

2104321075

The ZIP codes of Ilchester, MD, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Towns near Ilchester

The nearest larger towns are Catonsville (43,368 people, 3.5 mi), Columbia (104,338 people, 5.3 mi) and Ellicott City (75,257 people, 5.7 mi).

Towns near Ilchester
TownPopulationDistance
Elkridge 26,283 1.8 mi
Catonsville 43,368 3.5 mi
Arbutus 22,507 4.2 mi
Jessup 9,931 4.7 mi
Linthicum 11,313 5.2 mi
Columbia 104,338 5.3 mi
Lansdowne 7,876 5.4 mi
Ellicott City 75,257 5.7 mi
Savage 8,239 5.8 mi
Woodlawn 40,379 6.2 mi
Severn 58,402 6.6 mi
Baltimore Highlands 8,206 6.8 mi
Ferndale 17,529 7.2 mi
North Laurel 25,563 7.5 mi

More nearby: every ZIP code in Howard County · Maryland ZIP codes

Cite this page

zipcodes.pro. “Ilchester, MD ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/md/ilchester

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