• county
  • FIPS 17181
  • Largest town: Anna

Union County, Illinois

Union County had 16,886 residents in the Census Vintage 2024 estimate, on 413.4 square miles of land. It ranks 61st of 102 in Illinois by population and 71st by land area.

Population
16,886
#61 of 102 in Illinois · #1,984 in US
Area
413.4 sq mi
#71 of 102 in Illinois · #2,446 in US
Density
41 / sq mi
#57 of 102 in Illinois · #1,656 in US
Median household income
$64,452
#59 of 102 in Illinois · #1,419 in US

Census Vintage 2024 estimates · SAIPE 2023 income · 2024 Gazetteer land area

Union County within Illinois. Pin: Springfield.

Measure from here

Tools and pages that start from Union County

Union County population, land area and income

Union County had 16,886 residents in the Census Vintage 2024 estimate, on 413.4 square miles of land. It ranks 61st of 102 in Illinois by population and 71st by land area. That works out to 40.8 people per square mile, below the US average of 96.3, and below the national county median.

The median county-equivalent in Illinois has 24,447 residents; Union County is somewhat smaller.

Its SAIPE 2023 median household income of $64,452 is above the national county median among 3,143 counties with an estimate.

National rank among 3,144

Population

16,886

3144th1st

1984th of 3,144 (US)

Land area

413 sq mi

3144th1st

2446th of 3,144 (US)

Density

40.8 / sq mi

3144th1st

1656th of 3,144 (US)

Median household income

$64,452

3143rd1st

1419th of 3,143 (US)

Rank within Illinois (102)

Population

16,886

102nd1st

61st of 102 (IL)

Land area

413 sq mi

102nd1st

71st of 102 (IL)

Density

40.8 / sq mi

102nd1st

57th of 102 (IL)

Median household income

$64,452

102nd1st

59th of 102 (IL)

How Union County's population changed since 2020

Union County lost 412 residents between the July 2020 and July 2024 estimates, a drop of 2.4%. That ranks 69th of 102 in Illinois for growth. The median Illinois county changed by -1.7%, and the state as a whole by -0.7%.

Since the April 2020 estimates base, Union County recorded 649 births and 1,066 deaths, a natural change of -417. Net international migration added +141 and net domestic migration, people moving to or from other US counties, came to -182. The largest single component was natural change, which removed 417 people.

17.3k202017.0k202116.9k202216.9k202316.9k2024
Census Vintage 2024 county estimates for July 1 of each year. The axis starts above zero so year-to-year changes are visible.

Components of change, April 2020 to July 2024

Births
649
Deaths
1,066
Net international migration
+141
Net domestic migration
-182
Change, July 2023 to July 2024
+20

Where Union County is

The Census internal point of Union County is at 37.485700, -89.244600. It sits in UTM zone 16N. The map shades Illinois's 102 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Union County outlined. Dots are towns of 1,000+ people with residents in it.

Piatt County: -0.3%Hamilton County: -2.2%Williamson County: -0.1%Edgar County: -2.4%Macoupin County: -2.3%Marshall County: -1.3%Putnam County: +0.0%Richland County: -2.8%Washington County: -1.4%Lee County: -1.5%Douglas County: +0.2%Cook County: -1.6%Effingham County: -0.3%Edwards County: -3.6%Cass County: -2.0%Clay County: -3.4%Knox County: -2.2%LaSalle County: -0.9%Cumberland County: -1.3%Warren County: -3.7%Moultrie County: -0.9%Menard County: -2.5%Fayette County: -1.5%Boone County: -0.0%Lawrence County: -3.2%Marion County: -3.2%Champaign County: +3.0%Clark County: -2.4%Ford County: -0.4%Wayne County: -1.4%Logan County: -1.4%Grundy County: +2.5%Jasper County: -1.8%Crawford County: -1.3%McDonough County: -1.7%Clinton County: +0.5%Perry County: -3.0%Montgomery County: -2.2%Henry County: -2.0%Livingston County: -1.2%Scott County: -3.8%Alexander County: -11.2%Bureau County: -2.2%Brown County: +1.1%Mason County: -3.9%Calhoun County: -4.1%Greene County: -4.3%Coles County: -1.4%Kendall County: +8.2%Lake County: +0.7%Mercer County: -2.2%St. Clair County: -2.3%Wabash County: -3.0%Bond County: -1.7%DuPage County: +0.6%Gallatin County: -5.2%Stephenson County: -3.3%McHenry County: +1.9%White County: -3.0%Saline County: -3.9%Christian County: -2.2%Sangamon County: -1.0%Massac County: -3.6%Macon County: -2.9%Johnson County: -0.0%Jo Daviess County: -2.6%Peoria County: -1.0%DeKalb County: +1.0%Pope County: -1.5%De Witt County: -0.9%Schuyler County: -1.7%Fulton County: -3.1%Ogle County: -0.8%Jersey County: -1.6%Iroquois County: -3.3%Kankakee County: -0.9%Rock Island County: -1.1%Pulaski County: -5.8%Kane County: +0.9%Union County: -2.4%Whiteside County: -1.7%Woodford County: -0.3%Carroll County: -1.5%Adams County: -2.3%Hardin County: -2.6%Madison County: -1.0%Hancock County: -3.1%Monroe County: +0.0%Tazewell County: -1.1%Jackson County: -0.1%Vermilion County: -3.9%Randolph County: -0.6%McLean County: +0.5%Morgan County: -2.6%Shelby County: -1.7%Will County: +1.7%Winnebago County: -0.4%Jefferson County: -2.4%Stark County: -2.2%Henderson County: -4.5%Pike County: -2.6%Franklin County: -1.8%
Change 2020 to 2024
  1. < -3.0%
  2. < -2.2%
  3. < -1.4%
  4. < -0.3%
  5. ≥ -0.3%
no data

Orange pin: Union County internal point. Dark pin: Springfield.

Internal point

Decimal
37.485700, -89.244600
DMS
37°29'8.52"N 89°14'40.56"W
UTM
16N 301548.5E 4151121.2N
Geohash
dn8t30n44
Plus code
869GFQP4+75

Towns in Union County

3 incorporated places of 1,000+ people have residents in Union County, 6,860 people together, or 41% of the county. Each figure counts only the part of the town inside Union County; towns marked "part" extend into another county. The largest is Anna with 4,165.

  1. 01Anna4,165
  2. 02Jonesboro1,655
  3. 03Cobden1,040
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Union County

The Census 2024 county adjacency file lists 7 neighbors for Union County, including 2 across a state line. The most populous is Cape Girardeau County, MO, with 83,658 residents. Distances run between Census internal points in a straight line.

Distance to Springfield and the nearest big city

Springfield is 160.1 miles N of Union County's internal point in a straight line. The nearest place of 100,000 or more is St. Louis, MO (population 279,695), 96.3 miles away. The nearest place of 10,000 or more is Carbondale, IL (population 22,223), 16.4 miles away.

Union County FIPS code

The FIPS code of Union County is 17181: state code 17 for Illinois plus county code 181. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $64,452.

Questions people ask

What is the population of Union County, Illinois?

The Census Vintage 2024 estimate for July 1, 2024 is 16,886. That is down 412 people (2.4%) from the July 2020 estimate of 17,298.

What is the FIPS code of Union County?

17181. The first two digits (17) are Illinois; the last three (181) identify the county.

What is the largest town in Union County?

Anna, with 4,165 residents inside Union County in 2024.

Which counties border Union County?

7 county-equivalents border it in the Census 2024 adjacency file: Cape Girardeau County, MO; Williamson County, IL; Jackson County, IL; Perry County, MO; Johnson County, IL; Pulaski County, IL; Alexander County, IL.

Sources and data as of

Data as of: Census Vintage 2024 population estimates, 2024 Gazetteer land area and internal points, SAIPE 2023 median household income.

  1. 01Census Vintage 2024 county population estimates
  2. 02Census 2024 Gazetteer, counties
  3. 03Census SAIPE 2023 state and county estimates
  4. 04Census Vintage 2024 subcounty population estimates
  5. 05Census 2024 county adjacency file
  6. 06Census 2024 cartographic boundary file, counties (1:5,000,000)

How every number is computed: methodology. Spotted a wrong figure? Report an error.