Irish Population in Washington by County : 2025 Ranking & Insights

According to U.S. Census estimates, the Irish population in Washington totals 755,554. Every county in the state reports a non-zero population, with King County leading at 192,841, followed by Pierce County (94,618) and Snohomish County (76,404). This demographic analysis ranks all counties in Washington by their Irish population, offering insights into regional distribution patterns and highlighting county-level concentrations across the state.

Top 5 counties with the largest Irish population in Washington

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  • 1
    King County
    Irish population in King County is 192,841
    8.52% of King County population is Irish
  • 2
    Pierce County
    Irish population in Pierce County is 94,618
    10.24% of Pierce County population is Irish
  • 3
    Snohomish County
    Irish population in Snohomish County is 76,404
    9.15% of Snohomish County population is Irish
  • 4
    Spokane County
    Irish population in Spokane County is 71,344
    13.11% of Spokane County population is Irish
  • 5
    Clark County
    Irish population in Clark County is 51,344
    10.06% of Clark County population is Irish

Overview of Irish population in Washington

  • Population Count and Percentage: American Community Survey documents Washington with 755,554 Irish residents (9.8% of 7.7 million total state population), ranking the state at the 75th percentile nationally among U.S. jurisdictions for Irish demographic representation.
  • Comparison to State and National Averages: U.S. Census data records indicate Washington's Irish population of 9.8% exceeds the national average of 9.4% by a factor of 1.
  • Share of Total National Population: Official American Community Survey records show Washington hosts 755,554 Irish residents, representing 2.4% of the nation's total Irish population of 31.2 million, establishing the state as a significant demographic concentration center within national boundaries.
  • Population Density per Square Mile: U.S. Census Bureau's American Community Survey data show Washington maintains 11.4 Irish Americans per square mile compared to the national average of 8.8, indicating higher demographic concentration relative to national averages.
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39 Counties in Washington Ranked by Irish Population

View Methodology
American Community Survey data [1] show Irish populations across every county in Washington, with demographic distributions ranging from the highest population in King County to the lowest in $rank_n_geo_name. The table below provides broader statistics, including total population figures, density measures, and demographic distributions based on current ACS data for all counties included in this analysis*.
counties in Washington ranked by Irish population count
Rank by Irish Population
County
Irish Population
% of Total County Population
% of Total Washington Irish Population
5 Year Rank Trend
1 King County 192,841 8.52% 25.52%
2 Pierce County 94,618 10.24% 12.52%
3 Snohomish County 76,404 9.15% 10.11%
4 Spokane County 71,344 13.11% 9.44%
5 Clark County 51,344 10.06% 6.80%
6 Thurston County 35,690 12.03% 4.72%
7 Kitsap County 35,487 12.83% 4.70%
8 22,611 9.90% 2.99%
9 20,649 9.82% 2.73%
10 13,578 10.41% 1.80%
11 13,260 5.17% 1.76%
12 12,784 11.46% 1.69%
13 10,319 11.90% 1.37%
14 9,206 10.97% 1.22%
15 9,122 11.94% 1.21%
16 8,723 11.24% 1.15%
17 7,773 11.61% 1.03%
18 6,646 8.36% 0.88%
19 5,901 9.50% 0.78%
20 5,766 12.15% 0.76%
21 5,714 5.69% 0.76%
22 5,294 11.25% 0.70%
23 5,256 11.75% 0.70%
24 5,169 15.52% 0.68%
25 4,560 4.67% 0.60%
26 4,354 10.17% 0.58%
27 4,143 9.47% 0.55%
28 2,753 12.28% 0.36%
29 2,525 10.94% 0.33%
30 2,386 10.05% 0.32%
31 2,384 13.05% 0.32%
32 1,558 12.69% 0.21%
33 1,482 10.73% 0.20%
34 957 8.49% 0.13%
35 937 12.79% 0.12%
36 766 3.70% 0.10%
37 470 11.76% 0.06%
38 431 9.42% 0.06%
39 349 15.00% 0.05%
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Methodology

This ranking list is based on data from the American Community Survey (ACS) 5-Year Estimates, conducted by the U.S. Census Bureau. The ACS is one of the most reliable sources for understanding population trends across different locations, and it provides estimates for various racial and ethnic groups at city, county, state and all geography levels down to the Census block group.
This list ranks county in Washington by their Irish population, using the most recent ACS data available.

How the Census defines Irish population

The U.S. Census Bureau allows people to self-identify their ancestry, meaning individuals can write upto ancestries when responding to the survey. In this ranking, we include everyone who identifies as having Irish ancestry, whether alone or in combination with another ancestry.
Here are a few important things to know about how ancestry is reported:
  • Some people identify as Irish alone, while others identify as Irish along with another race (such as Irish and German).
  • We’ve used the “Irish alone or in any combination” category unless noted otherwise, which gives a broader picture of the Irish population in each area.

How We Ranked the Data

This ranking is based on the total number of people who identified as Irish alone or in combination in county. To provide additional context, we’ve also included two key percentages:
  1. % of Total County Population – This shows what percentage of the total state population identifies as Irish .
  2. % of Total Washington Irish Population – This tells us how much of the entire U.S. Irish population lives in that state.
To keep things simple, all population numbers have been rounded to the nearest whole number, and percentages are rounded to one decimal place. Because of rounding, some percentages may not add up to exactly 100%.

Things to Keep in Mind

Like all survey-based data, ACS estimates come with some limitations. Here are a few things to be aware of:
  • In places with very small Irish populations, the numbers may not be reported at all due to privacy protections or sampling variability in the survey.
  • Since the ACS is based on a sample, the numbers are estimates, not exact counts. That means they may slightly differ from other sources like the decennial U.S. Census.
  • County that don’t have any reported Irish population are not included in the ranking but are listed separately below for reference.
This ranking is meant to provide a clear, data-driven look at where Irish populations are most concentrated while keeping the numbers easy to understand.

Sources

  1. 2019-2023 5-Year Estimates.
  2. 2023.