53033 FipsDecoder
53055 County FIPS Code

San Juan County

Washington · County seat: Friday Harbor · Active county or equivalent

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FIPS code 53055 is San Juan County, Washington. With a population of 18,001 (2022 ACS estimate), it ranks #32 in Washington and #1973 nationally. The state FIPS code for Washington is 53. This code is used in Census Bureau, BLS, EPA, HUD, and USDA federal datasets to identify this county.

County FIPS

53055

State FIPS

53

WA

Population

18,001

2022 ACS · #1973 nationally

Density

103.5/mi²

people per sq mile

Land Area

174

sq miles

Urban/Rural

Nonmetro — completely rural

RUCC 9

How This FIPS Code Works

53 055
53 = State FIPS (Washington)
055 = County FIPS

The 5-digit FIPS code 53055 is formed by combining the 2-digit state identifier 53 (Washington) with the 3-digit county identifier 055. Together they uniquely identify San Juan County in every US federal dataset. No two counties share the same 5-digit FIPS code.

Census ACS Data for FIPS 53055

From the 2022 ACS 5-year estimates — the same values you'd retrieve by querying the Census API with county FIPS 53055.

Median Household Income

$76,745

ACS B19013_001E

Poverty Rate

11.0%

ACS B17001 (below poverty level)

Median Age

56.5

ACS B01002_001E

Adjacent Counties (5)

Counties that share a border with San Juan County. Useful for regional analysis — these are the geographies you'd typically include when studying labor markets, commuting zones, or environmental spillovers around FIPS 53055.

Federal Datasets Using Code 53055

FIPS code 53055 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 53055 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.

Census ACS API — Python 53055
import requests

url = "https://api.census.gov/data/2022/acs/acs5"
params = {
    "get":  "NAME,B19013_001E,B01003_001E",
    "for":  "county:055",
    "in":   "state:53",
    "key":  "YOUR_CENSUS_API_KEY",
}
r = requests.get(url, params=params)
data = r.json()  # [[header...], [San Juan County, Washington, income, pop, ...]
SQL — filtering by county FIPS 53055
-- 5-digit combined FIPS (state + county)
SELECT * FROM your_table WHERE county_fips = '53055';

-- Some datasets store state and county separately
SELECT * FROM your_table
WHERE state_fips = '53'
  AND county_fips = '055';

-- ⚠ Never cast to integer — leading zeros are lost:
-- county_fips = 53055 is WRONG for this county
R — tidycensus 53055
library(tidycensus)

get_acs(
  geography = "county",
  variables = c(income = "B19013_001E", pop = "B01003_001E"),
  state     = "53",
  county    = "055",
  year      = 2022
)
Zero-padding reminder: FIPS codes must always be stored and compared as zero-padded strings. 53 (not 53) and 055 (not 55) — losing the leading zeros is one of the most common data-join bugs in federal datasets. Full guide →

ZIP Codes in San Juan 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 San Juan County. Why FIPS ≠ ZIP →

ZIP Code % in county
98297 100.0%
98222 100.0%
98243 100.0%
98245 100.0%
98250 100.0%
98261 100.0%
98279 100.0%
98280 100.0%
98286 100.0%
98221 7.6%

Other Counties in Washington