20850 ZIP Code, Rockville, MD

20850 is a ZIP code in Rockville, Maryland in Montgomery County. It covers 14 square miles of land. The closest ZIP codes are 20851, 20877 and 20880. 50,353 people live here in 21,159 households, more than in 9 of every 10 Maryland ZIP codes. At about 3,567 people per square mile it has suburban density, and owners and renters are mixed (50% own). Median household income is $125,950, above the Maryland median of $103,678.

Quick facts

Key figures

MeasureValue
Residents50,353
Households21,159
Median household income$125,950
Income per person$68,066
Median age41.2
Homeowners50.3%
Median home value$714,400
Median rent$2,309
Bachelor's degree or higher67.5%
Average commute (minutes)30.1
Households with kids under 1825.8%
Moved in the past year18.0%
Below the poverty line6.9%
Broadband internet95.8%
Speak a non-English language at home42.6%

Household income

% of householdsValue
<$10K3.5%
$10–15K1.9%
$15–25K3.8%
$25–35K4.1%
$35–50K5.7%
$50–75K10.0%
$75–100K10.6%
$100–150K20.0%
$150–200K15.1%
$200K+25.2%

Age

% of all residentsValue
<1010.1%
10–199.7%
20–246.0%
25–3415.2%
35–4413.2%
45–5413.1%
55–6412.4%
65–749.7%
75+10.7%

Tenure

% of housing unitsValue
Owned, with mortgage31.6%
Owned outright16.1%
Rented46.8%
Vacant5.6%

Type of building

% of housing unitsValue
Detached house29.7%
Townhome19.4%
2–4 units1.8%
5–19 units15.5%
20+ units33.2%
Mobile / other0.3%

Businesses in 20850

2,728 business establishments with 61,746 employees (ZIP Codes Business Patterns 2023).

EDDM carrier routes

20850 has 46 USPS carrier routes with 23,039 residential and 2,848 business mailboxes. Open the EDDM route map.

Carrier routes in 20850

20850 has 46 USPS carrier routes (46 city (C)) with 23,039 residential and 2,848 business mailboxes. Routes range from 47 homes (C031) to 1,395 homes (C049); the median route has 436 homes. The Census counted 21,159 households in 20850 (2020–2024 average); USPS counts current mailboxes, including new and vacant homes.

Homes per routeRoutes
1–2496
250–49924
500–7498
750–9994
1,000–1,4994
1,500+0

Best routes in 20850 for…

Most businesses

For B2B offers: office supplies, cleaning, IT, catering and commercial services.

  1. Route C011 — USPS business mailboxes 286, 230 homes
  2. Route C031 — USPS business mailboxes 264, 47 homes
  3. Route C044 — USPS business mailboxes 219, 57 homes
  4. Route C008 — USPS business mailboxes 210, 343 homes
  5. Route C006 — USPS business mailboxes 199, 831 homes

Select these 5 routes on the route map

Every carrier route in 20850

RouteTypeHomesBusinessesEst. median incomeEst. ownersEst. families with kidsEst. moved in past year
C001City1,09356$75,758———
C002City4200$200,001+———
C004City254151$103,087———
C006City831199$24,018———
C007City3899$163,696———
C008City343210$24,018———
C009City772164$75,758———
C011City230286$98,851———
C012City6231$138,705———
C013City3380$130,658———
C014City200144$189,163———
C016City3061$173,853———
C017City4510$24,018———
C019City123179$105,159———
C020City178115$138,705———
C021City4942$182,879———
C022City4053$147,089———
C023City4973$147,089———
C024City4993$147,089———
C025City49841$181,187———
C026City4342$183,463———
C028City41916$163,696———
C030City458104$118,732———
C031City47264$76,590———
C032City53324$200,001+———
C033City359124$57,003———
C034City4091$200,001+———
C035City6653$119,623———
C036City9241$118,732———
C038City1,02338$115,269———
C039City52020$137,480———
C040City43684$200,001+———
C041City83049$200,001+———
C044City57219$98,851———
C046City43515$130,658———
C047City3821$153,272———
C048City25511$189,163———
C049City1,395117$118,732———
C050City7101$194,366———
C052City3211$198,337———
C055City72136$102,719———
C056City1,0011$102,719———
C058City52013$102,719———
C060City5192$138,705———
C061City366130$24,018———
C063City3564$105,757———

Income, owners, families and movers are estimates for each route (how we estimate them); mailbox counts are current USPS figures. Open 20850 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

Areas that include 20850

Where it ranks

Mail every home in 20850

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) 20850, which approximates the USPS ZIP code area. Census figures: American Community Survey 5-year estimates, 2020–2024.

Frequently asked questions

What city is 20850 in?
20850 is a Rockville, MD mailing address. By land area, 54% lies inside Rockville, 19% lies inside Travilah and 10% lies inside North Potomac; the rest is outside any Census-defined city or community.
What county is 20850 in?
20850 is in Montgomery County.
What is the population of 20850?
About 50,353 people (±1,773), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 51,045.
What is the median household income in 20850?
$125,950 (±$7,840), 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 20850?
46 USPS carrier routes with 23,039 residential and 2,848 business mailboxes (25,821 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.
What ZIP codes are near 20850?
The closest, measured center to center: 20851 (3.3 mi, Rockville), 20877 (3.6 mi, Gaithersburg), 20880 (3.6 mi, Washington Grove), 20852 (4 mi, North Bethesda), 20878 (4.1 mi, Gaithersburg) and 20855 (4.2 mi, Redland).

This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.