FIPS code 51610 is Falls Church city, Virginia. With a population of 14,576 (2022 ACS estimate), it ranks #101 in Virginia and #2174 nationally. Falls Church city is part of the Washington-Arlington-Alexandria, DC-VA-MD-WV. The state FIPS code for Virginia is 51. This code is used in Census Bureau, BLS, EPA, HUD, and USDA federal datasets to identify this county.
County FIPS
51610
Population
14,576
2022 ACS · #2174 nationally
Density
7,288.0/mi²
people per sq mile
Land Area
2
sq miles
Urban/Rural
Metro — 1M+ population
RUCC 1
How This FIPS Code Works
The 5-digit FIPS code 51610 is formed by combining the 2-digit state identifier 51 (Virginia) with the 3-digit county identifier 610. Together they uniquely identify Falls Church city in every US federal dataset. No two counties share the same 5-digit FIPS code.
Census ACS Data for FIPS 51610
From the 2022 ACS 5-year estimates — the same values you'd retrieve by querying the Census API with county FIPS 51610.
Median Household Income
$164,536
ACS B19013_001E
Poverty Rate
2.3%
ACS B17001 (below poverty level)
Median Age
38.8
ACS B01002_001E
Metropolitan Area
Adjacent Counties (2)
Counties that share a border with Falls Church city. Useful for regional analysis — these are the geographies you'd typically include when studying labor markets, commuting zones, or environmental spillovers around FIPS 51610.
Federal Datasets Using Code 51610
FIPS code 51610 appears as the county identifier in the following federal datasets. Analysts joining data across these sources use this code as the common geographic key.
Using FIPS Code 51610 in Code
Common patterns for querying federal datasets by this county's FIPS code. The leading zeros are significant — always treat FIPS codes as strings, not integers.
import requests
url = "https://api.census.gov/data/2022/acs/acs5"
params = {
"get": "NAME,B19013_001E,B01003_001E",
"for": "county:610",
"in": "state:51",
"key": "YOUR_CENSUS_API_KEY",
}
r = requests.get(url, params=params)
data = r.json() # [[header...], [Falls Church city, Virginia, income, pop, ...]-- 5-digit combined FIPS (state + county)
SELECT * FROM your_table WHERE county_fips = '51610';
-- Some datasets store state and county separately
SELECT * FROM your_table
WHERE state_fips = '51'
AND county_fips = '610';
-- ⚠ Never cast to integer — leading zeros are lost:
-- county_fips = 51610 is WRONG for this countylibrary(tidycensus)
get_acs(
geography = "county",
variables = c(income = "B19013_001E", pop = "B01003_001E"),
state = "51",
county = "610",
year = 2022
)ZIP Codes in Falls Church city
ZIP codes do not align perfectly with county boundaries — a single ZIP code can span multiple counties, and a county can contain parts of many ZIP codes. The ratios below (from the Census 2020 ZCTA relationship file) show the land area share of each ZCTA that falls within Falls Church city. Why FIPS ≠ ZIP →
| ZIP Code | % in county |
|---|---|
| 22046 | 66.3% |
| 22044 | 5.8% |
| 22043 | 1.2% |
| 22042 | 0.9% |