21043 ZIP Code, Ellicott City, MD
21043 is a ZIP code in Ellicott City, Maryland in Howard County. It covers 17 square miles of land. The closest ZIP codes are 21228, 21045 and 21075. 48,525 people live here in 17,568 households, more than in 9 of every 10 Maryland ZIP codes. At about 2,838 people per square mile it has suburban density, and owners and renters are mixed (67% own). Median household income is $148,125, above the Maryland median of $103,678.
Quick facts
- Mailing city: Ellicott City, MD
- County: Howard County
- Land area: 17 sq mi
- Population: 48,525
- Median household income: $148,125
- Carrier routes: 28 (18,948 homes)
Key figures
| Measure | Value |
|---|---|
| Residents | 48,525 |
| Households | 17,568 |
| Median household income | $148,125 |
| Income per person | $65,206 |
| Median age | 40.3 |
| Homeowners | 66.9% |
| Median home value | $620,900 |
| Median rent | $2,094 |
| Bachelor's degree or higher | 64.2% |
| Average commute (minutes) | 28.1 |
| Households with kids under 18 | 39.4% |
| Moved in the past year | 12.0% |
| Below the poverty line | 3.9% |
| Broadband internet | 97.6% |
| Speak a non-English language at home | 31.8% |
Household income
| % of households | Value |
|---|---|
| <$10K | 2.4% |
| $10–15K | 1.4% |
| $15–25K | 1.6% |
| $25–35K | 2.9% |
| $35–50K | 6.9% |
| $50–75K | 9.1% |
| $75–100K | 9.7% |
| $100–150K | 16.7% |
| $150–200K | 16.0% |
| $200K+ | 33.3% |
Age
| % of all residents | Value |
|---|---|
| <10 | 12.1% |
| 10–19 | 15.0% |
| 20–24 | 5.3% |
| 25–34 | 9.6% |
| 35–44 | 16.8% |
| 45–54 | 14.3% |
| 55–64 | 11.8% |
| 65–74 | 8.8% |
| 75+ | 6.3% |
Tenure
| % of housing units | Value |
|---|---|
| Owned, with mortgage | 46.8% |
| Owned outright | 18.3% |
| Rented | 31.8% |
| Vacant | 3.1% |
Type of building
| % of housing units | Value |
|---|---|
| Detached house | 43.3% |
| Townhome | 22.5% |
| 2–4 units | 1.4% |
| 5–19 units | 22.8% |
| 20+ units | 9.9% |
| Mobile / other | 0.1% |
Businesses in 21043
1,131 business establishments with 10,059 employees (ZIP Codes Business Patterns 2023).
- Professional, Scientific, and Technical Services: 395
- Health Care and Social Assistance: 131
- Retail Trade: 95
- Other Services (except Public Administration): 81
- Accommodation and Food Services: 78
- Finance and Insurance: 61
- Construction: 59
- Real Estate and Rental and Leasing: 57
EDDM carrier routes
21043 has 28 USPS carrier routes with 18,948 residential and 784 business mailboxes. Open the EDDM route map.
Carrier routes in 21043
21043 has 28 USPS carrier routes (16 city (C), 12 rural (R)) with 18,948 residential and 784 business mailboxes. Routes range from 402 homes (C018) to 1,141 homes (C033); the median route has 635 homes. The Census counted 17,568 households in 21043 (2020–2024 average); USPS counts current mailboxes, including new and vacant homes.
| Homes per route | Routes |
|---|---|
| 1–249 | 0 |
| 250–499 | 2 |
| 500–749 | 18 |
| 750–999 | 6 |
| 1,000–1,499 | 2 |
| 1,500+ | 0 |
Best routes in 21043 for…
Most businesses
For B2B offers: office supplies, cleaning, IT, catering and commercial services.
- Route C018 — USPS business mailboxes 177, 402 homes
- Route C028 — USPS business mailboxes 122, 610 homes
- Route C034 — USPS business mailboxes 115, 632 homes
- Route C008 — USPS business mailboxes 87, 696 homes
- Route C009 — USPS business mailboxes 72, 1,034 homes
Select these 5 routes on the route map
Every carrier route in 21043
| Route | Type | Homes | Businesses | Est. median income | Est. owners | Est. families with kids | Est. moved in past year |
|---|---|---|---|---|---|---|---|
| C002 | City | 552 | 11 | $200,001+ | — | — | — |
| C008 | City | 696 | 87 | $129,587 | — | — | — |
| C009 | City | 1,034 | 72 | $176,453 | — | — | — |
| C011 | City | 554 | 12 | $163,768 | — | — | — |
| C015 | City | 665 | 8 | $108,795 | — | — | — |
| C017 | City | 610 | 40 | $164,126 | — | — | — |
| C018 | City | 402 | 177 | $124,408 | — | — | — |
| C021 | City | 568 | 1 | $157,655 | — | — | — |
| C023 | City | 531 | 48 | $200,001+ | — | — | — |
| C028 | City | 610 | 122 | $68,931 | — | — | — |
| C029 | City | 641 | 0 | $164,728 | — | — | — |
| C033 | City | 1,141 | 6 | $108,795 | — | — | — |
| C034 | City | 632 | 115 | $164,728 | — | — | — |
| C037 | City | 454 | 1 | $200,001+ | — | — | — |
| C046 | City | 803 | 48 | $51,108 | — | — | — |
| C047 | City | 863 | 3 | $51,108 | — | — | — |
| R001 | Rural | 549 | 3 | $200,001+ | — | — | — |
| R009 | Rural | 844 | 1 | $103,067 | — | — | — |
| R011 | Rural | 606 | 4 | $200,001+ | — | — | — |
| R012 | Rural | 680 | 1 | $122,272 | — | — | — |
| R015 | Rural | 883 | 1 | $129,587 | — | — | — |
| R019 | Rural | 525 | 3 | $192,471 | — | — | — |
| R021 | Rural | 545 | 0 | $200,001+ | — | — | — |
| R022 | Rural | 613 | 3 | $200,001+ | — | — | — |
| R026 | Rural | 731 | 8 | $122,272 | — | — | — |
| R030 | Rural | 783 | 6 | $197,445 | — | — | — |
| R031 | Rural | 796 | 3 | $122,272 | — | — | — |
| R034 | Rural | 637 | 0 | $182,991 | — | — | — |
Income, owners, families and movers are estimates for each route (how we estimate them); mailbox counts are current USPS figures. Open 21043 on the EDDM route map.
How route demographics are estimated
Mailbox counts come from USPS; demographics are estimates
The number of homes and businesses on each carrier route is the current USPS EDDM count. The Census Bureau does not publish figures for carrier routes, so income, homeownership, ages, families, movers and housing age on a route are EDDM2GO estimates built from Census block groups (neighborhood areas of roughly 600 to 3,000 people).
How a route gets its figures: the block-group length-share method
We trace each route's streets every 25 meters and record which block group each stretch falls in. The route's homes are spread along its streets in proportion to length, so a route with 60% of its street length in one block group is assumed to have 60% of its homes there. Each block group then contributes its Census counts in proportion to the share of its housing units that sit on the route (capped at the whole block group). Medians are recalculated from the combined income, home-value and age brackets, the way the Census Bureau computes them, not averaged.
Margins of error
Census survey figures carry a margin of error at 90% confidence; we carry it through the calculation and show it as ±. Our margins treat the route-to-block-group split as exact, so the real uncertainty is larger. Routes with fewer than 100 estimated households, large margins, or streets we could not place are flagged.
Different years
USPS mailbox counts are current. Census figures are 5-year averages for 2020–2024, so a new subdivision may have more homes on the route today than the Census counted. Use the route figures to compare routes with each other, not as an exact head count.
Why some routes show identical figures
Two routes that run through the same block group get the same percentages and medians, because the Census publishes one set of figures for the whole block group. Their mailbox counts still differ, and those are exact.
Route and mailbox counts: USPS EDDM route data. Route demographics: EDDM2GO estimates from U.S. Census Bureau American Community Survey 5-year block-group data (2020–2024) and 2024 cartographic block-group boundaries. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.
Nearby ZIP codes
- 21228 — Catonsville CDP, MD (3.1 mi)
- 21045 — Columbia CDP, MD (3.7 mi)
- 21075 — Elkridge CDP, MD (4.5 mi)
- 21250 — Catonsville CDP, MD (4.8 mi)
- 21042 — Ellicott City CDP, MD (5.2 mi)
- 21044 — Columbia CDP, MD (5.4 mi)
- 21244 — Milford Mill CDP, MD (5.6 mi)
- 21046 — Columbia CDP, MD (5.9 mi)
Areas that include 21043
- Ellicott City, MD ZIP codes — 2 ZIP codes
- Ilchester, MD ZIP codes — 2 ZIP codes
- Howard County ZIP codes — 24 ZIP codes
- Maryland ZIP code data
Mail every home in 21043
Route counts on this page price as Full Service 6.5 × 9 postcards: we print, bundle by carrier route and hand the mailing to USPS. Prefer to take it to the Post Office yourself? Print only costs less and you pay postage at drop-off.
EDDM guides
ZIP code statistics describe the Census ZIP Code Tabulation Area (ZCTA) 21043, which approximates the USPS ZIP code area. Census figures: American Community Survey 5-year estimates, 2020–2024.
Frequently asked questions
- What city is 21043 in?
- 21043 is a Ellicott City, MD mailing address. By land area, 72% lies inside Ellicott City, 25% lies inside Ilchester and 3% lies inside Catonsville.
- What county is 21043 in?
- 21043 is in Howard County.
- What is the population of 21043?
- About 48,525 people (±2,109), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 48,775.
- What is the median household income in 21043?
- $148,125 (±$9,784), compared with $103,678 for Maryland as a whole. Half the households in the ZIP code earn more and half earn less.
- How many carrier routes and mailboxes are in 21043?
- 28 USPS carrier routes with 18,948 residential and 784 business mailboxes (19,734 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.
- What ZIP codes are near 21043?
- The closest, measured center to center: 21228 (3.1 mi, Catonsville), 21045 (3.7 mi, Columbia), 21075 (4.5 mi, Elkridge), 21250 (4.8 mi, Catonsville), 21042 (5.2 mi, Ellicott City) and 21044 (5.4 mi, Columbia).
This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.