20166 ZIP Code, Sterling, VA
20166 is a ZIP code in Sterling, Virginia in Loudoun County. It covers 27 square miles of land. The closest ZIP codes are 20148, 20164 and 20170. 14,949 people live here in 5,473 households. With about 550 people per square mile it is lightly settled, and owners and renters are mixed (50% own). Median household income is $133,401, above the Virginia median of $93,170; 43% of households have children under 18.
Quick facts
- Mailing city: Sterling, VA
- County: Loudoun County
- Land area: 27 sq mi
- Population: 14,949
- Median household income: $133,401
- Carrier routes: 14 (6,658 homes)
Key figures
| Measure | Value |
|---|---|
| Residents | 14,949 |
| Households | 5,473 |
| Median household income | $133,401 |
| Income per person | $58,048 |
| Median age | 34 |
| Homeowners | 49.5% |
| Median home value | $618,800 |
| Median rent | $2,362 |
| Bachelor's degree or higher | 65.3% |
| Average commute (minutes) | 27.9 |
| Households with kids under 18 | 43.4% |
| Moved in the past year | 15.0% |
| Below the poverty line | 4.1% |
| Broadband internet | 96.0% |
| Speak a non-English language at home | 52.7% |
Household income
| % of households | Value |
|---|---|
| <$10K | 2.5% |
| $10–15K | 0.2% |
| $15–25K | 1.3% |
| $25–35K | 4.5% |
| $35–50K | 5.0% |
| $50–75K | 7.9% |
| $75–100K | 9.5% |
| $100–150K | 26.5% |
| $150–200K | 15.5% |
| $200K+ | 27.3% |
Age
| % of all residents | Value |
|---|---|
| <10 | 16.0% |
| 10–19 | 11.8% |
| 20–24 | 6.3% |
| 25–34 | 17.8% |
| 35–44 | 19.6% |
| 45–54 | 12.3% |
| 55–64 | 10.0% |
| 65–74 | 4.5% |
| 75+ | 1.7% |
Tenure
| % of housing units | Value |
|---|---|
| Owned, with mortgage | 40.9% |
| Owned outright | 7.9% |
| Rented | 49.8% |
| Vacant | 1.4% |
Type of building
| % of housing units | Value |
|---|---|
| Detached house | 13.2% |
| Townhome | 40.5% |
| 2–4 units | 4.6% |
| 5–19 units | 19.7% |
| 20+ units | 22.0% |
| Mobile / other | 0.0% |
Businesses in 20166
1,902 business establishments with 67,063 employees (ZIP Codes Business Patterns 2023).
- Professional, Scientific, and Technical Services: 331
- Retail Trade: 220
- Construction: 196
- Other Services (except Public Administration): 173
- Transportation and Warehousing: 161
- Accommodation and Food Services: 146
- Administrative and Support and Waste Management and Remediation Services: 131
- Health Care and Social Assistance: 119
EDDM carrier routes
20166 has 14 USPS carrier routes with 6,658 residential and 2,577 business mailboxes. Open the EDDM route map.
Carrier routes in 20166
20166 has 14 USPS carrier routes (14 rural (R)) with 6,658 residential and 2,577 business mailboxes. Routes range from 1 homes (R024) to 1,007 homes (R031); the median route has 650 homes. The Census counted 5,473 households in 20166 (2020–2024 average); USPS counts current mailboxes, including new and vacant homes.
| Homes per route | Routes |
|---|---|
| 1–249 | 4 |
| 250–499 | 1 |
| 500–749 | 7 |
| 750–999 | 0 |
| 1,000–1,499 | 1 |
| 1,500+ | 0 |
Best routes in 20166 for…
Most businesses
For B2B offers: office supplies, cleaning, IT, catering and commercial services.
- Route R024 — USPS business mailboxes 454, 1 homes
- Route R012 — USPS business mailboxes 415, 225 homes
- Route R001 — USPS business mailboxes 385, 102 homes
- Route R017 — USPS business mailboxes 366, 0 homes
- Route R025 — USPS business mailboxes 284, 125 homes
Select these 5 routes on the route map
Every carrier route in 20166
| Route | Type | Homes | Businesses | Est. median income | Est. owners | Est. families with kids | Est. moved in past year |
|---|---|---|---|---|---|---|---|
| R001 | Rural | 102 | 385 | $143,842 | — | — | — |
| R009 | Rural | 683 | 26 | $186,111 | — | — | — |
| R012 | Rural | 225 | 415 | $162,977 | — | — | — |
| R017 | Rural | 0 | 366 | $125,932 | — | — | — |
| R018 | Rural | 573 | 91 | $125,932 | — | — | — |
| R019 | Rural | 397 | 264 | $162,977 | — | — | — |
| R022 | Rural | 729 | 9 | $127,319 | — | — | — |
| R024 | Rural | 1 | 454 | — | — | — | — |
| R025 | Rural | 125 | 284 | — | — | — | — |
| R027 | Rural | 713 | 65 | $89,959 | — | — | — |
| R030 | Rural | 748 | 0 | $200,001+ | — | — | — |
| R031 | Rural | 1,007 | 41 | $196,091 | — | — | — |
| R032 | Rural | 705 | 41 | $200,001+ | — | — | — |
| R034 | Rural | 650 | 136 | $200,001+ | — | — | — |
Income, owners, families and movers are estimates for each route (how we estimate them); mailbox counts are current USPS figures. Open 20166 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
- 20148 — Brambleton CDP, VA (4 mi)
- 20164 — Sterling CDP, VA (4.6 mi)
- 20170 — Herndon town, VA (4.6 mi)
- 20171 — Franklin Farm CDP, VA (4.7 mi)
- 20147 — Ashburn CDP, VA (5 mi)
- 20151 — Chantilly CDP, VA (5.1 mi)
- 20152 — South Riding CDP, VA (5.7 mi)
- 20190 — Reston CDP, VA (6.6 mi)
Areas that include 20166
- Ashburn, VA ZIP codes — 3 ZIP codes
- Sterling, VA ZIP codes — 3 ZIP codes
- Loudoun Valley Estates, VA ZIP codes — 2 ZIP codes
- Dulles Town Center, VA ZIP codes — 1 ZIP code
- Arcola, VA ZIP codes — 2 ZIP codes
- Oak Grove, VA ZIP codes — 2 ZIP codes
- Kincora, VA ZIP codes — 1 ZIP code
- Loudoun County ZIP codes — 20 ZIP codes
- Virginia ZIP code data
Where it ranks
- No. 5 of 17: highest share of households with children in Loudoun County
- No. 1 of 17: highest share of residents who moved in during the past year in Loudoun County
- No. 1 of 17: lowest median age in Loudoun County
- No. 3 of 17: fastest population growth in Loudoun County
Mail every home in 20166
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) 20166, which approximates the USPS ZIP code area. Census figures: American Community Survey 5-year estimates, 2020–2024.
Frequently asked questions
- What city is 20166 in?
- 20166 is a Sterling, VA mailing address. By land area, 9% lies inside Dulles Town Center, 8% lies inside Ashburn, 7% lies inside Arcola and 4% lies inside Oak Grove; the rest is outside any Census-defined city or community.
- What county is 20166 in?
- 20166 is in Loudoun County.
- What is the population of 20166?
- About 14,949 people (±1,299), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 14,164.
- What is the median household income in 20166?
- $133,401 (±$12,898), compared with $93,170 for Virginia as a whole. Half the households in the ZIP code earn more and half earn less.
- How many carrier routes and mailboxes are in 20166?
- 14 USPS carrier routes with 6,658 residential and 2,577 business mailboxes (9,240 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.
- What ZIP codes are near 20166?
- The closest, measured center to center: 20148 (4 mi, Brambleton), 20164 (4.6 mi, Sterling), 20170 (4.6 mi, Herndon), 20171 (4.7 mi, Franklin Farm), 20147 (5 mi, Ashburn) and 20151 (5.1 mi, Chantilly).
This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.