FIPS code 18175 is Washington County, Indiana. With a population of 28,133 (2022 ACS estimate), it ranks #57 in Indiana and #1527 nationally. Washington County is part of the Louisville/Jefferson County, KY-IN. The state FIPS code for Indiana is 18. This code is used in Census Bureau, BLS, EPA, HUD, and USDA federal datasets to identify this county.
County FIPS
18175
Population
28,133
2022 ACS · #1527 nationally
Density
54.8/mi²
people per sq mile
Land Area
514
sq miles
Urban/Rural
Metro — 1M+ population
RUCC 1
How This FIPS Code Works
The 5-digit FIPS code 18175 is formed by combining the 2-digit state identifier 18 (Indiana) with the 3-digit county identifier 175. Together they uniquely identify Washington County in every US federal dataset. No two counties share the same 5-digit FIPS code.
Census ACS Data for FIPS 18175
From the 2022 ACS 5-year estimates — the same values you'd retrieve by querying the Census API with county FIPS 18175.
Median Household Income
$60,695
ACS B19013_001E
Poverty Rate
13.1%
ACS B17001 (below poverty level)
Median Age
40.9
ACS B01002_001E
Metropolitan Area
Adjacent Counties (8)
Counties that share a border with Washington County. Useful for regional analysis — these are the geographies you'd typically include when studying labor markets, commuting zones, or environmental spillovers around FIPS 18175.
Federal Datasets Using Code 18175
FIPS code 18175 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 18175 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:175",
"in": "state:18",
"key": "YOUR_CENSUS_API_KEY",
}
r = requests.get(url, params=params)
data = r.json() # [[header...], [Washington County, Indiana, income, pop, ...]-- 5-digit combined FIPS (state + county)
SELECT * FROM your_table WHERE county_fips = '18175';
-- Some datasets store state and county separately
SELECT * FROM your_table
WHERE state_fips = '18'
AND county_fips = '175';
-- ⚠ Never cast to integer — leading zeros are lost:
-- county_fips = 18175 is WRONG for this countylibrary(tidycensus)
get_acs(
geography = "county",
variables = c(income = "B19013_001E", pop = "B01003_001E"),
state = "18",
county = "175",
year = 2022
)ZIP Codes in Washington 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 Washington County. Why FIPS ≠ ZIP →
| ZIP Code | % in county |
|---|---|
| 47167 | 100.0% |
| 47120 | 99.0% |
| 47108 | 97.3% |
| 47165 | 96.0% |
| 47125 | 51.9% |
| 47281 | 39.7% |
| 47170 | 36.8% |
| 47164 | 31.6% |
| 47106 | 4.0% |
| 47126 | 3.8% |
| 47452 | 0.5% |
| 47115 | 0.0% |