• county
  • FIPS 17177
  • Largest town: Freeport

Stephenson County, Illinois

Stephenson County had 43,088 residents in the Census Vintage 2024 estimate, on 564.3 square miles of land. It ranks 33rd of 102 in Illinois by population and 43rd by land area.

Population
43,088
#33 of 102 in Illinois · #1,134 in US
Area
564.3 sq mi
#43 of 102 in Illinois · #1,821 in US
Density
76 / sq mi
#31 of 102 in Illinois · #1,113 in US
Median household income
$64,926
#55 of 102 in Illinois · #1,381 in US

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

Stephenson County within Illinois. Pin: Springfield.

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Tools and pages that start from Stephenson County

Stephenson County population, land area and income

Stephenson County had 43,088 residents in the Census Vintage 2024 estimate, on 564.3 square miles of land. It ranks 33rd of 102 in Illinois by population and 43rd by land area. That works out to 76.4 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; Stephenson County is somewhat larger.

Its SAIPE 2023 median household income of $64,926 is above the national county median among 3,143 counties with an estimate.

National rank among 3,144

Population

43,088

3144th1st

1134th of 3,144 (US)

Land area

564 sq mi

3144th1st

1821st of 3,144 (US)

Density

76.4 / sq mi

3144th1st

1113th of 3,144 (US)

Median household income

$64,926

3143rd1st

1381st of 3,143 (US)

Rank within Illinois (102)

Population

43,088

102nd1st

33rd of 102 (IL)

Land area

564 sq mi

102nd1st

43rd of 102 (IL)

Density

76.4 / sq mi

102nd1st

31st of 102 (IL)

Median household income

$64,926

102nd1st

55th of 102 (IL)

How Stephenson County's population changed since 2020

Stephenson County lost 1,485 residents between the July 2020 and July 2024 estimates, a drop of 3.3%. That ranks 87th 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, Stephenson County recorded 1,759 births and 2,730 deaths, a natural change of -971. Net international migration added +178 and net domestic migration, people moving to or from other US counties, came to -818. The largest single component was natural change, which removed 971 people.

44.6k202044.1k202143.7k202243.3k202343.1k2024
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
1,759
Deaths
2,730
Net international migration
+178
Net domestic migration
-818
Change, July 2023 to July 2024
-259

Where Stephenson County is

The Census internal point of Stephenson County is at 42.349700, -89.666000. 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 Stephenson 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: Stephenson County internal point. Dark pin: Springfield.

Internal point

Decimal
42.349700, -89.666000
DMS
42°20'58.92"N 89°39'57.60"W
UTM
16N 280413.8E 4692047.0N
Geohash
dp80zte0y
Plus code
86JG88XM+VJ

Towns in Stephenson County

2 incorporated places of 1,000+ people have residents in Stephenson County, 25,806 people together, or 60% of the county. Each figure counts only the part of the town inside Stephenson County; towns marked "part" extend into another county. The largest is Freeport with 23,140.

  1. 01Freeport23,140
  2. 02Lena2,666
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Stephenson County

The Census 2024 county adjacency file lists 6 neighbors for Stephenson County, including 2 across a state line. The most populous is Winnebago County, IL, with 283,790 residents. Distances run between Census internal points in a straight line.

Distance to Springfield and the nearest big city

Springfield is 177.5 miles S of Stephenson County's internal point in a straight line. The nearest place of 100,000 or more is Rockford, IL (population 147,486), 31.4 miles away. The nearest place of 10,000 or more is Freeport, IL (population 23,140), 4.5 miles away.

Stephenson County FIPS code

The FIPS code of Stephenson County is 17177: state code 17 for Illinois plus county code 177. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $64,926.

Questions people ask

What is the population of Stephenson County, Illinois?

The Census Vintage 2024 estimate for July 1, 2024 is 43,088. That is down 1,485 people (3.3%) from the July 2020 estimate of 44,573.

What is the FIPS code of Stephenson County?

17177. The first two digits (17) are Illinois; the last three (177) identify the county.

What is the largest town in Stephenson County?

Freeport, with 23,140 residents inside Stephenson County in 2024.

Which counties border Stephenson County?

6 county-equivalents border it in the Census 2024 adjacency file: Winnebago County, IL; Ogle County, IL; Green County, WI; Jo Daviess County, IL; Lafayette County, WI; Carroll 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.