FIPS code 40041 is Delaware County, Oklahoma. With a population of 40,791 (2022 ACS estimate), it ranks #25 in Oklahoma and #1177 nationally. The state FIPS code for Oklahoma is 40. This code is used in Census Bureau, BLS, EPA, HUD, and USDA federal datasets to identify this county.
County FIPS
40041
Population
40,791
2022 ACS · #1177 nationally
Density
55.3/mi²
people per sq mile
Land Area
738
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 40041 is formed by combining the 2-digit state identifier 40 (Oklahoma) with the 3-digit county identifier 041. Together they uniquely identify Delaware County in every US federal dataset. No two counties share the same 5-digit FIPS code.
Census ACS Data for FIPS 40041
From the 2022 ACS 5-year estimates — the same values you'd retrieve by querying the Census API with county FIPS 40041.
Median Household Income
$53,290
ACS B19013_001E
Poverty Rate
19.1%
ACS B17001 (below poverty level)
Median Age
46.8
ACS B01002_001E
Adjacent Counties (7)
Counties that share a border with Delaware County. Useful for regional analysis — these are the geographies you'd typically include when studying labor markets, commuting zones, or environmental spillovers around FIPS 40041.
Federal Datasets Using Code 40041
FIPS code 40041 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 40041 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:041",
"in": "state:40",
"key": "YOUR_CENSUS_API_KEY",
}
r = requests.get(url, params=params)
data = r.json() # [[header...], [Delaware County, Oklahoma, income, pop, ...]-- 5-digit combined FIPS (state + county)
SELECT * FROM your_table WHERE county_fips = '40041';
-- Some datasets store state and county separately
SELECT * FROM your_table
WHERE state_fips = '40'
AND county_fips = '041';
-- ⚠ Never cast to integer — leading zeros are lost:
-- county_fips = 40041 is WRONG for this countylibrary(tidycensus)
get_acs(
geography = "county",
variables = c(income = "B19013_001E", pop = "B01003_001E"),
state = "40",
county = "041",
year = 2022
)ZIP Codes in Delaware 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 Delaware County. Why FIPS ≠ ZIP →
| ZIP Code | % in county |
|---|---|
| 74368 | 100.0% |
| 74346 | 100.0% |
| 74338 | 99.7% |
| 74344 | 97.3% |
| 74342 | 96.8% |
| 74359 | 94.7% |
| 74347 | 79.6% |
| 74364 | 66.0% |
| 74331 | 50.6% |
| 74365 | 27.1% |
| 74366 | 10.4% |
| 74370 | 6.9% |
| 74964 | 5.8% |