Data / Population / Sullivan County

Population in Sullivan County

Population in Sullivan County was 20,831 in 2025, according to the U.S. Census Bureau. That is up 0.7% from 2024. That is the 69th highest of 92 counties in 2025.

2025, persons20,831
Change on 2024+0.7%
Rank69th of 92Counties in Indiana ranked
Series high20,8312025
Series low20,6642022

Population in Sullivan County, 2020 to 2025

CSVChart (SVG)

20.7K20.7K20.8K20.8K20.9K2020202120222023202420252020: 20,820 persons2021: 20,783 persons2022: 20,664 persons2023: 20,714 persons2024: 20,693 persons2025: 20,831 persons
persons. Source: U.S. Census Bureau. Retrieved 2026-10-08, published 2026-03-26.
All 6 values
Periodpersons
202520,831
202420,693
202320,714
202220,664
202120,783
202020,820

Compared with Indiana and United States

Place2025
Sullivan County20,831
Indiana6,973,333
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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Questions

What is the population in Sullivan County?

Population in Sullivan County was 20,831 in 2025, according to the U.S. Census Bureau. That is up 0.7% from 2024. That is the 69th highest of 92 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 Sullivan County?

20,831 in 2025, the highest value since 2020 in this series.

More statistics for Sullivan County

All statistics for Sullivan County