Warren County
New Jersey · County seat: Belvidere · Active county or equivalent
FIPS code 34041 is Warren County, New Jersey. With a population of 109,739 (2022 ACS estimate), it ranks #19 in New Jersey and #556 nationally. Warren County is part of the Allentown-Bethlehem-Easton, PA-NJ. The state FIPS code for New Jersey is 34. This code is used in Census Bureau, BLS, EPA, HUD, and USDA federal datasets to identify this county.
County FIPS
34041
Population
109,739
2022 ACS · #556 nationally
Density
307.5/mi²
people per sq mile
Land Area
357
sq miles
Urban/Rural
Metro — 250K–1M population
RUCC 2
How This FIPS Code Works
The 5-digit FIPS code 34041 is formed by combining the 2-digit state identifier 34 (New Jersey) with the 3-digit county identifier 041. Together they uniquely identify Warren County in every US federal dataset. No two counties share the same 5-digit FIPS code.
Census ACS Data for FIPS 34041
From the 2022 ACS 5-year estimates — the same values you'd retrieve by querying the Census API with county FIPS 34041.
Median Household Income
$92,620
ACS B19013_001E
Poverty Rate
7.7%
ACS B17001 (below poverty level)
Median Age
44.0
ACS B01002_001E
Metropolitan Area
Adjacent Counties (6)
Counties that share a border with Warren County. Useful for regional analysis — these are the geographies you'd typically include when studying labor markets, commuting zones, or environmental spillovers around FIPS 34041.
Federal Datasets Using Code 34041
FIPS code 34041 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 34041 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:34",
"key": "YOUR_CENSUS_API_KEY",
}
r = requests.get(url, params=params)
data = r.json() # [[header...], [Warren County, New Jersey, income, pop, ...]
-- 5-digit combined FIPS (state + county)
SELECT * FROM your_table WHERE county_fips = '34041';
-- Some datasets store state and county separately
SELECT * FROM your_table
WHERE state_fips = '34'
AND county_fips = '041';
-- ⚠ Never cast to integer — leading zeros are lost:
-- county_fips = 34041 is WRONG for this county
library(tidycensus)
get_acs(
geography = "county",
variables = c(income = "B19013_001E", pop = "B01003_001E"),
state = "34",
county = "041",
year = 2022
)
ZIP Codes in Warren 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 Warren County. Why FIPS ≠ ZIP →
| ZIP Code | % in county |
|---|---|
| 07820 | 100.0% |
| 07831 | 100.0% |
| 07832 | 100.0% |
| 07833 | 100.0% |
| 07838 | 100.0% |
| 07844 | 100.0% |
| 07846 | 100.0% |
| 07863 | 100.0% |
| 07880 | 100.0% |
| 08865 | 100.0% |
| 08886 | 100.0% |
| 07823 | 100.0% |
| 07825 | 97.8% |
| 07882 | 95.1% |
| 07840 | 76.4% |
| 07865 | 64.6% |
| 08802 | 42.2% |
| 08804 | 39.8% |
| 07821 | 16.6% |
| 08827 | 9.7% |
| 07860 | 6.1% |
| 07874 | 2.8% |