Stephenson County
Illinois · County seat: Freeport · Active county or equivalent
FIPS code 17177 is Stephenson County, Illinois. With a population of 44,482 (2022 ACS estimate), it ranks #33 in Illinois and #1097 nationally. Stephenson County is part of the Freeport, IL. The state FIPS code for Illinois is 17. This code is used in Census Bureau, BLS, EPA, HUD, and USDA federal datasets to identify this county.
County FIPS
17177
Population
44,482
2022 ACS · #1097 nationally
Density
78.8/mi²
people per sq mile
Land Area
565
sq miles
Urban/Rural
Nonmetro — urban 20K+, adjacent to metro
RUCC 4
How This FIPS Code Works
The 5-digit FIPS code 17177 is formed by combining the 2-digit state identifier 17 (Illinois) with the 3-digit county identifier 177. Together they uniquely identify Stephenson County in every US federal dataset. No two counties share the same 5-digit FIPS code.
Census ACS Data for FIPS 17177
From the 2022 ACS 5-year estimates — the same values you'd retrieve by querying the Census API with county FIPS 17177.
Median Household Income
$57,527
ACS B19013_001E
Poverty Rate
13.3%
ACS B17001 (below poverty level)
Median Age
45.6
ACS B01002_001E
Metropolitan Area
Adjacent Counties (6)
Counties that share a border with Stephenson County. Useful for regional analysis — these are the geographies you'd typically include when studying labor markets, commuting zones, or environmental spillovers around FIPS 17177.
Federal Datasets Using Code 17177
FIPS code 17177 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 17177 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:177",
"in": "state:17",
"key": "YOUR_CENSUS_API_KEY",
}
r = requests.get(url, params=params)
data = r.json() # [[header...], [Stephenson County, Illinois, income, pop, ...]-- 5-digit combined FIPS (state + county)
SELECT * FROM your_table WHERE county_fips = '17177';
-- Some datasets store state and county separately
SELECT * FROM your_table
WHERE state_fips = '17'
AND county_fips = '177';
-- ⚠ Never cast to integer — leading zeros are lost:
-- county_fips = 17177 is WRONG for this countylibrary(tidycensus)
get_acs(
geography = "county",
variables = c(income = "B19013_001E", pop = "B01003_001E"),
state = "17",
county = "177",
year = 2022
)ZIP Codes in Stephenson 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 Stephenson County. Why FIPS ≠ ZIP →
| ZIP Code | % in county |
|---|---|
| 61060 | 100.0% |
| 61013 | 100.0% |
| 61018 | 100.0% |
| 61050 | 100.0% |
| 61027 | 100.0% |
| 61032 | 100.0% |
| 61070 | 100.0% |
| 61067 | 100.0% |
| 61089 | 96.0% |
| 61048 | 91.2% |
| 61062 | 91.1% |
| 61044 | 65.7% |
| 61019 | 62.0% |
| 61039 | 62.0% |
| 61007 | 43.3% |
| 61078 | 17.5% |
| 61063 | 16.4% |
| 61087 | 7.0% |
| 61047 | 1.7% |