Menard County
Illinois · County seat: Petersburg · Active county or equivalent
FIPS code 17129 is Menard County, Illinois. With a population of 12,284 (2022 ACS estimate), it ranks #83 in Illinois and #2322 nationally. Menard County is part of the Springfield, 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
17129
Population
12,284
2022 ACS · #2322 nationally
Density
39.1/mi²
people per sq mile
Land Area
314
sq miles
Urban/Rural
Metro — under 250K population
RUCC 3
How This FIPS Code Works
The 5-digit FIPS code 17129 is formed by combining the 2-digit state identifier 17 (Illinois) with the 3-digit county identifier 129. Together they uniquely identify Menard County in every US federal dataset. No two counties share the same 5-digit FIPS code.
Census ACS Data for FIPS 17129
From the 2022 ACS 5-year estimates — the same values you'd retrieve by querying the Census API with county FIPS 17129.
Median Household Income
$84,846
ACS B19013_001E
Poverty Rate
7.9%
ACS B17001 (below poverty level)
Median Age
42.8
ACS B01002_001E
Metropolitan Area
Adjacent Counties (4)
Counties that share a border with Menard County. Useful for regional analysis — these are the geographies you'd typically include when studying labor markets, commuting zones, or environmental spillovers around FIPS 17129.
Federal Datasets Using Code 17129
FIPS code 17129 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 17129 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:129",
"in": "state:17",
"key": "YOUR_CENSUS_API_KEY",
}
r = requests.get(url, params=params)
data = r.json() # [[header...], [Menard County, Illinois, income, pop, ...]-- 5-digit combined FIPS (state + county)
SELECT * FROM your_table WHERE county_fips = '17129';
-- Some datasets store state and county separately
SELECT * FROM your_table
WHERE state_fips = '17'
AND county_fips = '129';
-- ⚠ Never cast to integer — leading zeros are lost:
-- county_fips = 17129 is WRONG for this countylibrary(tidycensus)
get_acs(
geography = "county",
variables = c(income = "B19013_001E", pop = "B01003_001E"),
state = "17",
county = "129",
year = 2022
)ZIP Codes in Menard 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 Menard County. Why FIPS ≠ ZIP →
| ZIP Code | % in county |
|---|---|
| 62642 | 100.0% |
| 62688 | 100.0% |
| 62675 | 98.0% |
| 62613 | 85.4% |
| 62673 | 69.3% |
| 62666 | 23.1% |
| 62693 | 2.9% |
| 62677 | 1.7% |