• county
  • FIPS 17025
  • Largest town: Flora

Clay County, Illinois

Clay County had 12,821 residents in the Census Vintage 2024 estimate, on 468.4 square miles of land. It ranks 80th of 102 in Illinois by population and 59th by land area.

Population
12,821
#80 of 102 in Illinois · #2,231 in US
Area
468.4 sq mi
#59 of 102 in Illinois · #2,197 in US
Density
27 / sq mi
#77 of 102 in Illinois · #2,003 in US
Median household income
$54,837
#93 of 102 in Illinois · #2,338 in US

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

Clay County within Illinois. Pin: Springfield.

Measure from here

Tools and pages that start from Clay County

Clay County population, land area and income

Clay County had 12,821 residents in the Census Vintage 2024 estimate, on 468.4 square miles of land. It ranks 80th of 102 in Illinois by population and 59th by land area. That works out to 27.4 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; Clay County is somewhat smaller.

Its SAIPE 2023 median household income of $54,837 is below the national county median among 3,143 counties with an estimate.

National rank among 3,144

Population

12,821

3144th1st

2231st of 3,144 (US)

Land area

468 sq mi

3144th1st

2197th of 3,144 (US)

Density

27.4 / sq mi

3144th1st

2003rd of 3,144 (US)

Median household income

$54,837

3143rd1st

2338th of 3,143 (US)

Rank within Illinois (102)

Population

12,821

102nd1st

80th of 102 (IL)

Land area

468 sq mi

102nd1st

59th of 102 (IL)

Density

27.4 / sq mi

102nd1st

77th of 102 (IL)

Median household income

$54,837

102nd1st

93rd of 102 (IL)

How Clay County's population changed since 2020

Clay County lost 452 residents between the July 2020 and July 2024 estimates, a drop of 3.4%. That ranks 89th 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, Clay County recorded 626 births and 809 deaths, a natural change of -183. Net international migration added +2 and net domestic migration, people moving to or from other US counties, came to -290. The largest single component was domestic migration, which removed 290 people.

13.3k202013.2k202113.1k202212.9k202312.8k2024
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
626
Deaths
809
Net international migration
+2
Net domestic migration
-290
Change, July 2023 to July 2024
-124

Where Clay County is

The Census internal point of Clay County is at 38.746800, -88.482300. 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 Clay 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: Clay County internal point. Dark pin: Springfield.

Internal point

Decimal
38.746800, -88.482300
DMS
38°44'48.48"N 88°28'56.28"W
UTM
16N 371185.7E 4289722.3N
Geohash
dnch6t9hk
Plus code
86CHPGW9+P3

Towns in Clay County

2 incorporated places of 1,000+ people have residents in Clay County, 5,754 people together, or 45% of the county. Each figure counts only the part of the town inside Clay County; towns marked "part" extend into another county. The largest is Flora with 4,647.

  1. 01Flora4,647
  2. 02Louisville1,107
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Clay County

The Census 2024 county adjacency file lists 6 neighbors for Clay County. The most populous is Marion County, IL, with 36,437 residents. Distances run between Census internal points in a straight line.

Distance to Springfield and the nearest big city

Springfield is 94.9 miles NW of Clay County's internal point in a straight line. The nearest place of 100,000 or more is Evansville, IN (population 115,395), 73.4 miles away. The nearest place of 10,000 or more is Effingham, IL (population 12,434), 26.1 miles away.

Clay County FIPS code

The FIPS code of Clay County is 17025: state code 17 for Illinois plus county code 025. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $54,837.

Questions people ask

What is the population of Clay County, Illinois?

The Census Vintage 2024 estimate for July 1, 2024 is 12,821. That is down 452 people (3.4%) from the July 2020 estimate of 13,273.

What is the FIPS code of Clay County?

17025. The first two digits (17) are Illinois; the last three (025) identify the county.

What is the largest town in Clay County?

Flora, with 4,647 residents inside Clay County in 2024.

Which counties border Clay County?

6 county-equivalents border it in the Census 2024 adjacency file: Marion County, IL; Effingham County, IL; Fayette County, IL; Wayne County, IL; Richland County, IL; Jasper 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.