• county
  • FIPS 17097
  • Largest town: Waukegan

Lake County, Illinois

Lake County had 718,604 residents in the Census Vintage 2024 estimate, on 443.7 square miles of land. It ranks 3rd of 102 in Illinois by population and 61st by land area.

Population
718,604
#3 of 102 in Illinois · #98 in US
Area
443.7 sq mi
#61 of 102 in Illinois · #2,289 in US
Density
1,620 / sq mi
#3 of 102 in Illinois · #98 in US
Median household income
$108,349
#2 of 102 in Illinois · #74 in US

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

Lake County within Illinois. Pin: Springfield.

Measure from here

Tools and pages that start from Lake County

Lake County population, land area and income

Lake County had 718,604 residents in the Census Vintage 2024 estimate, on 443.7 square miles of land. It ranks 3rd of 102 in Illinois by population and 61st by land area. That works out to 1,619.6 people per square mile, 16.8 times the US average of 96.3, and in the top tenth nationally.

The median county-equivalent in Illinois has 24,447 residents, so Lake County is 29.4 times that size.

Its SAIPE 2023 median household income of $108,349 is in the top tenth among 3,143 counties with an estimate.

National rank among 3,144

Population

718,604

3144th1st

98th of 3,144 (US)

Land area

444 sq mi

3144th1st

2289th of 3,144 (US)

Density

1,619.6 / sq mi

3144th1st

98th of 3,144 (US)

Median household income

$108,349

3143rd1st

74th of 3,143 (US)

Rank within Illinois (102)

Population

718,604

102nd1st

3rd of 102 (IL)

Land area

444 sq mi

102nd1st

61st of 102 (IL)

Density

1,619.6 / sq mi

102nd1st

3rd of 102 (IL)

Median household income

$108,349

102nd1st

2nd of 102 (IL)

How Lake County's population changed since 2020

Lake County gained 5,178 residents between the July 2020 and July 2024 estimates, a rise of 0.7%. That ranks 9th 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, Lake County recorded 28,432 births and 22,503 deaths, a natural change of +5,929. Net international migration added +18,050 and net domestic migration, people moving to or from other US counties, came to -20,287. The largest single component was domestic migration, which removed 20,287 people.

713.4k2020712.7k2021712.1k2022714.2k2023718.6k2024
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
28,432
Deaths
22,503
Net international migration
+18,050
Net domestic migration
-20,287
Change, July 2023 to July 2024
+4,397

Where Lake County is

The Census internal point of Lake County is at 42.186000, -87.805900. 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 Lake 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: Lake County internal point. Dark pin: Springfield.

Internal point

Decimal
42.186000, -87.805900
DMS
42°11'9.60"N 87°48'21.24"W
UTM
16N 433451.8E 4670742.2N
Geohash
dp3xcztxq
Plus code
86JJ55PV+CJ

Towns in Lake County

48 incorporated places of 1,000+ people have residents in Lake County, 635,356 people together, or 88% of the county. Each figure counts only the part of the town inside Lake County; towns marked "part" extend into another county. The largest is Waukegan with 88,570.

  1. 01Waukegan88,570
  2. 02Mundelein32,641
  3. 03Highland Park30,794
  4. 04North Chicago30,639
  5. 05Gurnee30,546
  6. 06Buffalo Grove (part)29,563
  7. 07Round Lake Beach27,091
  8. 08Vernon Hills27,002
  9. 09Zion24,583
  10. 10Grayslake21,262
  11. 11Libertyville20,643
  12. 12Lake Zurich19,960
  13. 13Lake Forest19,642
  14. 14Deerfield (part)18,670
  15. 15Round Lake18,654
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Lake County

The Census 2024 county adjacency file lists 6 neighbors for Lake County, including 4 across a state line. The most populous is Cook County, IL, with 5,182,617 residents. Distances run between Census internal points in a straight line.

Distance to Springfield and the nearest big city

Springfield is 192.0 miles SSW of Lake County's internal point in a straight line. The nearest place of 100,000 or more is Chicago, IL (population 2,721,308), 24.9 miles away. The nearest place of 10,000 or more is Highland Park, IL (population 30,794), 0.4 miles away.

Lake County FIPS code

The FIPS code of Lake County is 17097: state code 17 for Illinois plus county code 097. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $108,349.

Questions people ask

What is the population of Lake County, Illinois?

The Census Vintage 2024 estimate for July 1, 2024 is 718,604. That is up 5,178 people (0.7%) from the July 2020 estimate of 713,426.

What is the FIPS code of Lake County?

17097. The first two digits (17) are Illinois; the last three (097) identify the county.

What is the largest town in Lake County?

Waukegan, with 88,570 residents inside Lake County in 2024.

Which counties border Lake County?

6 county-equivalents border it in the Census 2024 adjacency file: Cook County, IL; McHenry County, IL; Kenosha County, WI; Berrien County, MI; Allegan County, MI; Van Buren County, MI.

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.