Oklahoma County
Oklahoma · County seat: Oklahoma City · Active county or equivalent
FIPS code 40109 is Oklahoma County, Oklahoma. With a population of 795,822 (2022 ACS estimate), it ranks #1 in Oklahoma and #78 nationally. Oklahoma County is part of the Oklahoma City, OK. 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
40109
Population
795,822
2022 ACS · #78 nationally
Density
1,122.7/mi²
people per sq mile
Land Area
709
sq miles
Urban/Rural
Metro — 1M+ population
RUCC 1
How This FIPS Code Works
The 5-digit FIPS code 40109 is formed by combining the 2-digit state identifier 40 (Oklahoma) with the 3-digit county identifier 109. Together they uniquely identify Oklahoma County in every US federal dataset. No two counties share the same 5-digit FIPS code.
Census ACS Data for FIPS 40109
From the 2022 ACS 5-year estimates — the same values you'd retrieve by querying the Census API with county FIPS 40109.
Median Household Income
$62,505
ACS B19013_001E
Poverty Rate
15.8%
ACS B17001 (below poverty level)
Median Age
35.1
ACS B01002_001E
Metropolitan Area
Adjacent Counties (6)
Counties that share a border with Oklahoma County. Useful for regional analysis — these are the geographies you'd typically include when studying labor markets, commuting zones, or environmental spillovers around FIPS 40109.
Federal Datasets Using Code 40109
FIPS code 40109 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 40109 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:109",
"in": "state:40",
"key": "YOUR_CENSUS_API_KEY",
}
r = requests.get(url, params=params)
data = r.json() # [[header...], [Oklahoma County, Oklahoma, income, pop, ...]-- 5-digit combined FIPS (state + county)
SELECT * FROM your_table WHERE county_fips = '40109';
-- Some datasets store state and county separately
SELECT * FROM your_table
WHERE state_fips = '40'
AND county_fips = '109';
-- ⚠ Never cast to integer — leading zeros are lost:
-- county_fips = 40109 is WRONG for this countylibrary(tidycensus)
get_acs(
geography = "county",
variables = c(income = "B19013_001E", pop = "B01003_001E"),
state = "40",
county = "109",
year = 2022
)ZIP Codes in Oklahoma 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 Oklahoma County. Why FIPS ≠ ZIP →
| ZIP Code | % in county |
|---|---|
| 73130 | 100.0% |
| 73162 | 100.0% |
| 73008 | 100.0% |
| 73012 | 100.0% |
| 73013 | 100.0% |
| 73151 | 100.0% |
| 73131 | 100.0% |
| 73145 | 100.0% |
| 73142 | 100.0% |
| 73049 | 100.0% |
| 73141 | 100.0% |
| 73066 | 100.0% |
| 73003 | 100.0% |
| 73084 | 100.0% |
| 73097 | 100.0% |
| 73102 | 100.0% |
| 73103 | 100.0% |
| 73104 | 100.0% |
| 73105 | 100.0% |
| 73106 | 100.0% |
| 73107 | 100.0% |
| 73108 | 100.0% |
| 73109 | 100.0% |
| 73110 | 100.0% |
| 73111 | 100.0% |
| 73112 | 100.0% |
| 73114 | 100.0% |
| 73115 | 100.0% |
| 73116 | 100.0% |
| 73117 | 100.0% |
Showing top 30 of 55 ZIP codes by residential address share.