• county
  • FIPS 17095
  • Largest town: Galesburg

Knox County, Illinois

Knox County had 48,716 residents in the Census Vintage 2024 estimate, on 716.4 square miles of land. It ranks 29th of 102 in Illinois by population and 21st by land area.

Population
48,716
#29 of 102 in Illinois · #1,026 in US
Area
716.4 sq mi
#21 of 102 in Illinois · #1,264 in US
Density
68 / sq mi
#35 of 102 in Illinois · #1,197 in US
Median household income
$57,569
#87 of 102 in Illinois · #2,079 in US

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

Knox County within Illinois. Pin: Springfield.

Measure from here

Tools and pages that start from Knox County

Knox County population, land area and income

Knox County had 48,716 residents in the Census Vintage 2024 estimate, on 716.4 square miles of land. It ranks 29th of 102 in Illinois by population and 21st by land area. That works out to 68.0 people per square mile, below the US average of 96.3, and above the national county median.

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

Its SAIPE 2023 median household income of $57,569 is below the national county median among 3,143 counties with an estimate.

National rank among 3,144

Population

48,716

3144th1st

1026th of 3,144 (US)

Land area

716 sq mi

3144th1st

1264th of 3,144 (US)

Density

68.0 / sq mi

3144th1st

1197th of 3,144 (US)

Median household income

$57,569

3143rd1st

2079th of 3,143 (US)

Rank within Illinois (102)

Population

48,716

102nd1st

29th of 102 (IL)

Land area

716 sq mi

102nd1st

21st of 102 (IL)

Density

68.0 / sq mi

102nd1st

35th of 102 (IL)

Median household income

$57,569

102nd1st

87th of 102 (IL)

How Knox County's population changed since 2020

Knox County lost 1,090 residents between the July 2020 and July 2024 estimates, a drop of 2.2%. That ranks 62nd 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, Knox County recorded 2,063 births and 3,163 deaths, a natural change of -1,100. Net international migration added +976 and net domestic migration, people moving to or from other US counties, came to -1,149. The largest single component was domestic migration, which removed 1,149 people.

49.8k202049.3k202148.7k202248.7k202348.7k2024
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
2,063
Deaths
3,163
Net international migration
+976
Net domestic migration
-1,149
Change, July 2023 to July 2024
+53

Where Knox County is

The Census internal point of Knox County is at 40.930900, -90.213800. It sits in UTM zone 15N. The map shades Illinois's 102 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Knox 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: Knox County internal point. Dark pin: Springfield.

Internal point

Decimal
40.930900, -90.213800
DMS
40°55'51.24"N 90°12'49.68"W
UTM
15N 734581.5E 4534824.7N
Geohash
9zrbg5hrf
Plus code
86GFWQJP+9F

Towns in Knox County

3 incorporated places of 1,000+ people have residents in Knox County, 35,000 people together, or 72% of the county. Each figure counts only the part of the town inside Knox County; towns marked "part" extend into another county. The largest is Galesburg with 29,289.

  1. 01Galesburg29,289
  2. 02Abingdon2,871
  3. 03Knoxville2,840
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Knox County

The Census 2024 county adjacency file lists 6 neighbors for Knox County. The most populous is Peoria County, IL, with 179,630 residents. Distances run between Census internal points in a straight line.

Distance to Springfield and the nearest big city

Springfield is 84.8 miles SSE of Knox County's internal point in a straight line. The nearest place of 100,000 or more is Peoria, IL (population 111,696), 33.6 miles away. The nearest place of 10,000 or more is Galesburg, IL (population 29,289), 8.6 miles away.

Knox County FIPS code

The FIPS code of Knox County is 17095: state code 17 for Illinois plus county code 095. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $57,569.

Questions people ask

What is the population of Knox County, Illinois?

The Census Vintage 2024 estimate for July 1, 2024 is 48,716. That is down 1,090 people (2.2%) from the July 2020 estimate of 49,806.

What is the FIPS code of Knox County?

17095. The first two digits (17) are Illinois; the last three (095) identify the county.

What is the largest town in Knox County?

Galesburg, with 29,289 residents inside Knox County in 2024.

Which counties border Knox County?

6 county-equivalents border it in the Census 2024 adjacency file: Peoria County, IL; Henry County, IL; Fulton County, IL; Warren County, IL; Mercer County, IL; Stark 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.