• county
  • FIPS 17201
  • Largest town: Rockford

Winnebago County, Illinois

Winnebago County had 283,790 residents in the Census Vintage 2024 estimate, on 513.1 square miles of land. It ranks 7th of 102 in Illinois by population and 51st by land area.

Population
283,790
#7 of 102 in Illinois · #256 in US
Area
513.1 sq mi
#51 of 102 in Illinois · #2,031 in US
Density
553 / sq mi
#6 of 102 in Illinois · #260 in US
Median household income
$65,795
#52 of 102 in Illinois · #1,317 in US

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

Winnebago County within Illinois. Pin: Springfield.

Measure from here

Tools and pages that start from Winnebago County

Winnebago County population, land area and income

Winnebago County had 283,790 residents in the Census Vintage 2024 estimate, on 513.1 square miles of land. It ranks 7th of 102 in Illinois by population and 51st by land area. That works out to 553.1 people per square mile, 5.7 times the US average of 96.3, and in the top tenth nationally.

The median county-equivalent in Illinois has 24,447 residents, so Winnebago County is 11.6 times that size.

Its SAIPE 2023 median household income of $65,795 is above the national county median among 3,143 counties with an estimate.

National rank among 3,144

Population

283,790

3144th1st

256th of 3,144 (US)

Land area

513 sq mi

3144th1st

2031st of 3,144 (US)

Density

553.1 / sq mi

3144th1st

260th of 3,144 (US)

Median household income

$65,795

3143rd1st

1317th of 3,143 (US)

Rank within Illinois (102)

Population

283,790

102nd1st

7th of 102 (IL)

Land area

513 sq mi

102nd1st

51st of 102 (IL)

Density

553.1 / sq mi

102nd1st

6th of 102 (IL)

Median household income

$65,795

102nd1st

52nd of 102 (IL)

How Winnebago County's population changed since 2020

Winnebago County lost 1,173 residents between the July 2020 and July 2024 estimates, a drop of 0.4%. That ranks 23rd 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, Winnebago County recorded 13,821 births and 14,543 deaths, a natural change of -722. Net international migration added +4,236 and net domestic migration, people moving to or from other US counties, came to -5,159. The largest single component was domestic migration, which removed 5,159 people.

285.0k2020283.4k2021282.1k2022282.2k2023283.8k2024
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
13,821
Deaths
14,543
Net international migration
+4,236
Net domestic migration
-5,159
Change, July 2023 to July 2024
+1,576

Where Winnebago County is

The Census internal point of Winnebago County is at 42.337400, -89.161200. 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 Winnebago 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: Winnebago County internal point. Dark pin: Springfield.

Internal point

Decimal
42.337400, -89.161200
DMS
42°20'14.64"N 89°09'40.32"W
UTM
16N 321959.2E 4689500.5N
Geohash
dp88g56c1
Plus code
86JG8RPQ+XG

Towns in Winnebago County

10 incorporated places of 1,000+ people have residents in Winnebago County, 228,066 people together, or 80% of the county. Each figure counts only the part of the town inside Winnebago County; towns marked "part" extend into another county. The largest is Rockford with 147,484.

  1. 01Rockford (part)147,484
  2. 02Machesney Park22,839
  3. 03Loves Park (part)22,018
  4. 04Roscoe10,981
  5. 05South Beloit7,983
  6. 06Rockton7,861
  7. 07Winnebago2,907
  8. 08Cherry Valley (part)2,552
  9. 09Pecatonica2,058
  10. 10Durand1,383
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Winnebago County

The Census 2024 county adjacency file lists 6 neighbors for Winnebago County, including 2 across a state line. The most populous is Rock County, WI, with 165,461 residents. Distances run between Census internal points in a straight line.

Distance to Springfield and the nearest big city

Springfield is 178.5 miles S of Winnebago County's internal point in a straight line. The nearest place of 100,000 or more is Rockford, IL (population 147,486), 7.3 miles away. The nearest place of 10,000 or more is Machesney Park, IL (population 22,839), 7.3 miles away.

Winnebago County FIPS code

The FIPS code of Winnebago County is 17201: state code 17 for Illinois plus county code 201. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $65,795.

Questions people ask

What is the population of Winnebago County, Illinois?

The Census Vintage 2024 estimate for July 1, 2024 is 283,790. That is down 1,173 people (0.4%) from the July 2020 estimate of 284,963.

What is the FIPS code of Winnebago County?

17201. The first two digits (17) are Illinois; the last three (201) identify the county.

What is the largest town in Winnebago County?

Rockford, with 147,484 residents inside Winnebago County in 2024 (147,486 across all 2 counties it spans).

Which counties border Winnebago County?

6 county-equivalents border it in the Census 2024 adjacency file: Rock County, WI; DeKalb County, IL; Boone County, IL; Ogle County, IL; Stephenson County, IL; Green County, WI.

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.