Data / Population / Washington County

Population in Washington County

Population in Washington County was 13,564 in 2025, according to the U.S. Census Bureau. That is down 0.1% from 2024. That is the 75th highest of 102 counties in 2025.

2025, persons13,564
Change on 2024-0.1%
Rank75th of 102Counties in Illinois ranked
Series high13,7292020
Series low13,5642025

Population in Washington County, 2020 to 2025

CSVChart (SVG)

13.6K13.6K13.7K13.7K13.8K2020202120222023202420252020: 13,729 persons2021: 13,654 persons2022: 13,651 persons2023: 13,574 persons2024: 13,579 persons2025: 13,564 persons
persons. Source: U.S. Census Bureau. Retrieved 2026-10-08, published 2026-03-26.
All 6 values
Periodpersons
202513,564
202413,579
202313,574
202213,651
202113,654
202013,729

Compared with Illinois and United States

Place2025
Washington County13,564
Illinois12,719,141
United States341,784,857

Rankings

Definition

Resident population. Spain and the EU: 1 January, with Spanish figures from the official municipal register (Padrón). United States: Census Bureau population estimates for 1 July. Other countries and the World: World Bank mid-year estimates, which count all residents regardless of legal status or citizenship.

For Denmark, Statistics Denmark counts the registered resident population on 1 January. Greenland and the Faroe Islands are excluded. The annual series selects the first-quarter reference date from FOLK1A. The World Bank series exists for every country, so use it (through compare) to rank countries on one basis.

How to cite

U.S. Census Bureau. Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-08.

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What is the latest population in Washington County? Cite the source.
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Questions

What is the population in Washington County?

Population in Washington County was 13,564 in 2025, according to the U.S. Census Bureau. That is down 0.1% from 2024. That is the 75th highest of 102 counties in 2025.

Where does this figure come from?

U.S. Census Bureau. Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). Retrieved by Invokely on 2026-10-08.

What was the highest population in Washington County?

13,729 in 2020, the highest value since 2020 in this series.

More statistics for Washington County

All statistics for Washington County