FIPS code 23019 is Penobscot County, Maine. With a population of 152,640 (2022 ACS estimate), it ranks #3 in Maine and #442 nationally. Penobscot County is part of the Bangor, ME. The state FIPS code for Maine is 23. This code is used in Census Bureau, BLS, EPA, HUD, and USDA federal datasets to identify this county.
County FIPS
23019
Population
152,640
2022 ACS · #442 nationally
Density
44.9/mi²
people per sq mile
Land Area
3,397
sq miles
Urban/Rural
Metro — under 250K population
RUCC 3
How This FIPS Code Works
The 5-digit FIPS code 23019 is formed by combining the 2-digit state identifier 23 (Maine) with the 3-digit county identifier 019. Together they uniquely identify Penobscot County in every US federal dataset. No two counties share the same 5-digit FIPS code.
Census ACS Data for FIPS 23019
From the 2022 ACS 5-year estimates — the same values you'd retrieve by querying the Census API with county FIPS 23019.
Median Household Income
$59,438
ACS B19013_001E
Poverty Rate
13.4%
ACS B17001 (below poverty level)
Median Age
42.4
ACS B01002_001E
Metropolitan Area
Adjacent Counties (6)
Counties that share a border with Penobscot County. Useful for regional analysis — these are the geographies you'd typically include when studying labor markets, commuting zones, or environmental spillovers around FIPS 23019.
Federal Datasets Using Code 23019
FIPS code 23019 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 23019 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:019",
"in": "state:23",
"key": "YOUR_CENSUS_API_KEY",
}
r = requests.get(url, params=params)
data = r.json() # [[header...], [Penobscot County, Maine, income, pop, ...]
-- 5-digit combined FIPS (state + county)
SELECT * FROM your_table WHERE county_fips = '23019';
-- Some datasets store state and county separately
SELECT * FROM your_table
WHERE state_fips = '23'
AND county_fips = '019';
-- ⚠ Never cast to integer — leading zeros are lost:
-- county_fips = 23019 is WRONG for this county
library(tidycensus)
get_acs(
geography = "county",
variables = c(income = "B19013_001E", pop = "B01003_001E"),
state = "23",
county = "019",
year = 2022
)
ZIP Codes in Penobscot 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 Penobscot County. Why FIPS ≠ ZIP →
| ZIP Code | % in county |
|---|---|
| 04401 | 100.0% |
| 04410 | 100.0% |
| 04411 | 100.0% |
| 04412 | 100.0% |
| 04417 | 100.0% |
| 04418 | 100.0% |
| 04419 | 100.0% |
| 04422 | 100.0% |
| 04427 | 100.0% |
| 04428 | 100.0% |
| 04765 | 100.0% |
| 04777 | 100.0% |
| 04928 | 100.0% |
| 04932 | 100.0% |
| 04939 | 100.0% |
| 04953 | 100.0% |
| 04969 | 100.0% |
| 04430 | 100.0% |
| 04434 | 100.0% |
| 04435 | 100.0% |
| 04444 | 100.0% |
| 04448 | 100.0% |
| 04449 | 100.0% |
| 04450 | 100.0% |
| 04453 | 100.0% |
| 04455 | 100.0% |
| 04456 | 100.0% |
| 04457 | 100.0% |
| 04460 | 100.0% |
| 04461 | 100.0% |
Showing top 30 of 47 ZIP codes by residential address share.