3 Southern Illinois counties among those losing greatest percentage of population
.JPG "Here’s what to know about Illinois population trends from 2020 to 2024, including a county-level map.")
Three Southern Illinois counties were among the top five in the state for population decline over a recent four-year period, according to data from the U.S. Census Bureau. The state’s population also decreased as a whole.
The bureau’s estimates of the resident population change from April 1, 2020, to July 1, 2024, released in March, show Alexander, Pulaski, Gallatin, Henderson and Greene counties lost the greatest percentage of residents.
Alexander, Pulaski and Gallatin are also among the poorest counties in Illinois, according to a report from finance website SmartAsset, which considered factors such as median income, median home value and investment income.
From 2020 to 2024 overall, Illinois lost 88,930 residents statewide, but gained in 2023 and 2024. Only 15 of Illinois’ 102 counties saw net population gains from 2020 to 2024.
Those who moved from Illinois to other states in 2023 most often moved to Indiana, Florida, Wisconsin, Texas and California, Fox 2 reported in October.
Here’s what to know about the Illinois counties with the greatest percentage loss of residents, as well as population trends in the metro-east.
Top 5 Illinois counties for population decline
1. Alexander County
Alexander County saw the greatest percentage decline in population from 2020 to 2024, losing 578 residents or 11.18% of the county’s population. The county is located at the southernmost point of Illinois, and its poverty rate is more than twice the statewide figure.
Since the county is smaller than many in Illinois, it took fewer than 600 residents leaving to land it the No. 1 spot for percentage of population decline. The Census Bureau estimates the county has 4,594 residents as of July 1, 2024.
Alexander County was organized out of Union County in 1819, according to the county’s government website, and its county seat is Cairo.
Median household income: $43,523
Poverty rate: 25.8%
Median monthly housing costs with a mortgage: $1,191
Median gross monthly rent: $540
2. Pulaski County
Pulaski County, located directly east of Alexander, lost 300 residents, or 5.79% of its population. Similarly to Alexander, Pulaski also has a much higher poverty rate than Illinois as a whole. Pulaski had 4,879 residents as of July 1, 2024, according to Census Bureau estimates.
Pulaski is located along the Ohio River, and its county seat is Mound City.
Median household income: $43,227
Poverty rate: 22.4%
Median monthly housing costs with a mortgage: $970
Median gross monthly rent: $625
3. Gallatin County
Gallatin County, also located in southern Illinois, lost 255 residents, or 5.16% of its population. The Census Bureau estimates Gallatin had 4,690 residents in 2024.
The county seat is Shawneetown, and Gallatin’s website highlights its historic significance and hiking opportunities.
Median household income: $54,626
Poverty rate: 17.5%
Median monthly housing costs with a mortgage: $1,103
Median gross monthly rent: $500
4. Henderson County
Henderson County, located in the western region of Illinois, lost 287 residents, or 4.53% of its population. The county had 6,048 residents in 2024, the Census Bureau estimates.
Henderson’s county seat is Oquawka. The Illinois Secretary of State’s Office reports the county was named after Kentucky’s Henderson County “through the influence of emigrants from that county.”
Median household income: $65,651
Poverty rate: 13.2%
Median monthly housing costs with a mortgage: $1,167
Median gross monthly rent: $834
5. Greene County
Greene County, just north of the metro-east, lost 518 residents, or 4.34% of its population. The Census Bureau estimates it had 11,417 residents in 2024.
The county has several sites on The National Register of Historic Places, as well as nature to explore.
Median household income: $60,976
Poverty rate: 13.8%
Median monthly housing costs with a mortgage: $1,128
Median gross monthly rent: $800
How is the metro-east population doing?
Although St. Clair County didn’t top the list for the counties with the greatest percentage population decrease, the county lost the second greatest number of residents at 5,921. Cook County lost the greatest number of residents, at 84,455.
Calhoun: Lost 179 residents, or 4.07% of population
St. Clair: Lost 5,921 residents or 2.3% of population
Macoupin: Lost 1,029 residents, or 2.29% of population
Bond: Lost 280 residents, or 1.66% of population
Jersey: Lost 342 residents, or 1.59% of population
Madison: Lost 2,732 residents or 1.03% of population
Monroe: Gained 16 residents, or 0.05% of population
Clinton: Gained 174 residents, or 0.47% of population
Note: An AI tool assisted with organizing the data for this story. A Belleville News-Democrat journalist reviewed the data and wrote the story. Percentages of population gain and decline are rounded to the nearest hundredth.
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