FIPS code 21009 is Barren County, Kentucky. With a population of 44,511 (2022 ACS estimate), it ranks #25 in Kentucky and #1096 nationally. Barren County is part of the Glasgow, KY. The state FIPS code for Kentucky is 21. This code is used in Census Bureau, BLS, EPA, HUD, and USDA federal datasets to identify this county.
County FIPS
21009
Population
44,511
2022 ACS · #1096 nationally
Density
91.3/mi²
people per sq mile
Land Area
488
sq miles
Urban/Rural
Nonmetro — urban 2.5K–19.9K, adjacent to metro
RUCC 6
How This FIPS Code Works
The 5-digit FIPS code 21009 is formed by combining the 2-digit state identifier 21 (Kentucky) with the 3-digit county identifier 009. Together they uniquely identify Barren County in every US federal dataset. No two counties share the same 5-digit FIPS code.
Census ACS Data for FIPS 21009
From the 2022 ACS 5-year estimates — the same values you'd retrieve by querying the Census API with county FIPS 21009.
Median Household Income
$48,141
ACS B19013_001E
Poverty Rate
21.1%
ACS B17001 (below poverty level)
Median Age
40.2
ACS B01002_001E
Metropolitan Area
Adjacent Counties (6)
Counties that share a border with Barren County. Useful for regional analysis — these are the geographies you'd typically include when studying labor markets, commuting zones, or environmental spillovers around FIPS 21009.
Federal Datasets Using Code 21009
FIPS code 21009 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 21009 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:009",
"in": "state:21",
"key": "YOUR_CENSUS_API_KEY",
}
r = requests.get(url, params=params)
data = r.json() # [[header...], [Barren County, Kentucky, income, pop, ...]-- 5-digit combined FIPS (state + county)
SELECT * FROM your_table WHERE county_fips = '21009';
-- Some datasets store state and county separately
SELECT * FROM your_table
WHERE state_fips = '21'
AND county_fips = '009';
-- ⚠ Never cast to integer — leading zeros are lost:
-- county_fips = 21009 is WRONG for this countylibrary(tidycensus)
get_acs(
geography = "county",
variables = c(income = "B19013_001E", pop = "B01003_001E"),
state = "21",
county = "009",
year = 2022
)ZIP Codes in Barren County
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 Barren County. Why FIPS ≠ ZIP →
| ZIP Code | % in county |
|---|---|
| 42123 | 100.0% |
| 42130 | 100.0% |
| 42131 | 100.0% |
| 42156 | 100.0% |
| 42141 | 100.0% |
| 42127 | 85.1% |
| 42160 | 44.7% |
| 42133 | 32.2% |
| 42171 | 24.6% |
| 42166 | 24.4% |
| 42154 | 12.8% |
| 42749 | 6.4% |