County in Illinois, United States
County in Illinois
Adams County is the westernmostcounty in theU.S. state ofIllinois . As of the2020 United States census , the population was 65,737.[ 2] county seat isQuincy .[ 3] MO Micropolitan Statistical Area .
Adams County was formed in 1825 out ofPike County . Its name is in honor of the sixthPresident of the United States ,John Quincy Adams .
Quincy, Illinois Climate chart (explanation ) J
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According to theU.S. Census Bureau , the county has a total area of 871 square miles (2,260 km2 ), of which 855 square miles (2,210 km2 ) is land and 16 square miles (41 km2 ) (1.9%) is water.[ 6]
National protected area [ edit ] Climate and weather [ edit ] In recent years, average temperatures in the county seat of Quincy have ranged from a low of 16 °F (−9 °C) in January to a high of 88 °F (31 °C) in July, although a record low of −21 °F (−29 °C) was recorded in January 1979 and a record high of 105 °F (41 °C) was recorded in July 2005. Average monthly precipitation ranged from 1.36 inches (35 mm) in January to 4.61 inches (117 mm) in May.[ 5]
2000 Census Age Pyramid for Adams County. Historical population Census Pop. Note %± 1830 2,186 — 1840 14,476 562.2% 1850 26,508 83.1% 1860 41,323 55.9% 1870 56,362 36.4% 1880 59,135 4.9% 1890 61,888 4.7% 1900 67,058 8.4% 1910 64,588 −3.7% 1920 62,188 −3.7% 1930 62,784 1.0% 1940 65,229 3.9% 1950 64,690 −0.8% 1960 68,467 5.8% 1970 70,861 3.5% 1980 71,622 1.1% 1990 66,090 −7.7% 2000 68,277 3.3% 2010 67,103 −1.7% 2020 65,737 −2.0% 2024 (est.) 64,109 [ 7] −2.5% U.S. Decennial Census[ 8] [ 9] [ 10] [ 11] [ 2]
As of the2020 census , the county had a population of 65,737. The median age was 41.3 years, 22.4% of residents were under the age of 18, and 20.5% of residents were 65 years of age or older. For every 100 females there were 95.8 males, and for every 100 females age 18 and over there were 93.4 males age 18 and over.[ 12]
The racial makeup of the county was 89.5%White , 3.8%Black or African American , 0.2%American Indian and Alaska Native , 0.8%Asian , 0.1%Native Hawaiian andPacific Islander , 0.8% from some other race, and 4.9% fromtwo or more races .Hispanic or Latino residents of any race comprised 2.0% of the population.[ 13]
66.1% of residents lived in urban areas, while 33.9% lived in rural areas.[ 14]
There were 27,313 households in the county, of which 27.4% had children under the age of 18 living in them. Of all households, 47.3% were married-couple households, 18.0% were households with a male householder and no spouse or partner present, and 27.2% were households with a female householder and no spouse or partner present. About 31.1% of all households were made up of individuals and 14.0% had someone living alone who was 65 years of age or older.[ 12]
There were 30,235 housing units, of which 9.7% were vacant. Among occupied housing units, 71.5% were owner-occupied and 28.5% were renter-occupied. The homeowner vacancy rate was 1.8% and the rental vacancy rate was 11.1%.[ 12]
Racial and ethnic composition [ edit ] Adams County, Illinois – Racial and ethnic composition Note: the US Census treats Hispanic/Latino as an ethnic category. This table excludes Latinos from the racial categories and assigns them to a separate category. Hispanics/Latinos may be of any race. Race / Ethnicity(NH = Non-Hispanic ) Pop 1980[ 15] Pop 1990[ 16] Pop 2000[ 17] Pop 2010[ 18] Pop 2020[ 19] % 1980 % 1990 % 2000 % 2010 % 2020 White alone (NH)69,274 63,729 64,611 62,414 58,389 96.72% 96.43% 94.63% 93.01% 88.82% Black or African American alone (NH)1,697 1,684 2,077 2,288 2,464 2.37% 2.55% 3.04% 3.41% 3.75% Native American orAlaska Native alone (NH)74 97 102 100 92 0.10% 0.15% 0.15% 0.15% 0.14% Asian alone (NH)160 247 269 430 500 0.22% 0.37% 0.39% 0.64% 0.76% Native Hawaiian orPacific Islander alone (NH)x[ 20] x[ 21] 8 12 33 x x 0.01% 0.02% 0.05% Other race alone (NH)114 68 45 75 223 0.16% 0.10% 0.07% 0.11% 0.34% Mixed race or Multiracial (NH)x[ 22] x[ 23] 598 1,008 2,749 x x 0.88% 1.50% 4.18% Hispanic or Latino (any race)303 265 567 776 1,287 0.42% 0.40% 0.83% 1.16% 1.96% Total 71,622 66,090 68,277 67,103 65,737 100.00% 100.00% 100.00% 100.00% 100.00%
[ edit ] The median income for a household in the county was $55,052 and the median income for a family was $72,091. Males had a median income of $41,852 versus $29,404 for females. The per capita income for the county was $31,035. About 9.4% of families and 12.5% of the population were below thepoverty line , including 17.7% of those under age 18 and 9.9% of those age 65 or over.[ 24]
Adams County, Illinois. Community Community Population Total Water Land Pop. Camp Point village 1,121 1.27 0.00 1.27 885.47 Clayton village 639 0.89 0.01 0.88 722.85 Coatsburg village 150 0.13 0.00 0.13 1,136.36 Columbus village 114 0.22 0.00 0.22 520.55 Golden village 648 0.64 0.00 0.64 1,009.35 La Prairie village 42 0.19 0.00 0.19 217.62 Liberty village 543 0.39 0.00 0.39 1,388.75 Lima village 148 0.14 0.00 0.14 1,096.30 Loraine village 300 0.84 0.00 0.84 355.45 Mendon village 872 0.86 0.00 0.86 1,017.50 Payson village 1,025 1.17 0.00 1.17 876.07 Plainville village 271 0.23 0.00 0.23 1,153.19 Quincy (seat)city 39,463 15.81 0.04 15.77 2,503.20 Ursa village 609 0.69 0.00 0.69 882.61 Adams County county 65,737 871 16 855 75
Census-designated places [ edit ] Unincorporated communities [ edit ] Adams County is divided into twenty-threetownships :
United States presidential election results for Adams County, Illinois[ 25] Year Republican Democratic Third party(ies) No. % No. % No. % 1892 6,081 41.98% 7,746 53.48% 657 4.54% 1896 8,447 50.26% 8,025 47.75% 336 2.00% 1900 8,047 46.81% 8,844 51.44% 301 1.75% 1904 7,277 49.06% 6,149 41.45% 1,408 9.49% 1908 7,233 44.34% 8,294 50.84% 787 4.82% 1912 3,780 26.50% 6,952 48.74% 3,531 24.76% 1916 11,858 44.23% 14,268 53.22% 682 2.54% 1920 12,852 57.07% 7,222 32.07% 2,447 10.87% 1924 9,985 40.92% 8,628 35.35% 5,791 23.73% 1928 15,590 53.59% 13,215 45.42% 288 0.99% 1932 10,134 32.00% 21,098 66.62% 437 1.38% 1936 13,114 39.18% 18,857 56.33% 1,502 4.49% 1940 18,480 50.86% 17,361 47.78% 492 1.35% 1944 15,564 52.87% 13,733 46.65% 142 0.48% 1948 14,329 48.67% 14,960 50.81% 152 0.52% 1952 19,652 59.60% 13,301 40.34% 21 0.06% 1956 19,569 63.12% 11,402 36.78% 32 0.10% 1960 18,674 55.70% 14,827 44.22% 28 0.08% 1964 13,993 43.30% 18,321 56.70% 0 0.00% 1968 17,444 54.33% 11,521 35.88% 3,143 9.79% 1972 20,731 69.46% 9,055 30.34% 60 0.20% 1976 18,189 59.67% 11,926 39.12% 370 1.21% 1980 19,842 62.17% 10,606 33.23% 1,469 4.60% 1984 20,225 65.99% 10,336 33.72% 88 0.29% 1988 15,831 53.29% 13,768 46.34% 111 0.37% 1992 13,529 42.84% 11,748 37.20% 6,302 19.96% 1996 13,836 48.70% 11,336 39.90% 3,239 11.40% 2000 17,331 57.56% 12,197 40.51% 581 1.93% 2004 20,834 66.19% 10,511 33.39% 132 0.42% 2008 18,711 60.55% 11,794 38.17% 397 1.28% 2012 20,416 66.51% 9,648 31.43% 633 2.06% 2016 22,790 70.54% 7,676 23.76% 1,844 5.71% 2020 24,220 72.24% 8,633 25.75% 674 2.01% 2024 23,161 72.61% 8,111 25.43% 628 1.97%
Adams County, positioned in a primarilyrural section ofIllinois , isculturally isolated from Chicago, and therefore is somewhat moreconservative than the state's northeastern corner. Quincy, the county seat, is home to a high number ofsocially conservative Catholics [ 26] Quincy University , aprivate Catholicliberal arts college, and the Western Catholic Union.
The county is part of the historic belt of German settlement extending into theMissouri Rhineland . Since it was antagonistic to theYankee northeast of Illinois, it voted solidly Democratic until 1892. After being a swing county in the first half of the twentieth century, Adams County has been a Republican stronghold. It has gone Republican in all but four presidential elections since 1920, all but one of which was a 400-vote Democratic landslide. The county last supported a Democrat in 1964, when it voted forLyndon Johnson . The county regularly supports the Republicans at the state level as well; it has not supported a Democrat for Governor of Illinois sinceAdlai Stevenson II in 1948. Additionally, five of the six countywide elected officials in Adams County are Republicans, with a Democrat holding the position of Circuit Clerk.[ 27] [ 28] Barack Obama in his 2004 Senate campaign, he lost it by wide margins in both of his presidential bids.
The county is part ofIllinois's 15th congressional district , currently represented by RepublicanMary Miller . For theIllinois House of Representatives , the county is located in the 94th district, represented by RepublicanRandy Frese . The county is located in the 47th district of theIllinois Senate , represented by RepublicanJil Tracy .
Unified school districts [ edit ] School districts covering sections of the county include:[ 29]
Colleges and universities [ edit ] ^ "County Population Totals and Components of Change: 2020–2024" .United States Census Bureau . U.S. Department of Commerce. March 2025. RetrievedAugust 31, 2025 .^a b "State & County QuickFacts" . United States Census Bureau. Archived fromthe original on June 6, 2011. RetrievedJuly 3, 2014 .^ "Find a County" . National Association of Counties. Archived fromthe original on May 31, 2011. RetrievedJune 7, 2011 .^ White, Jesse.Origin and Evolution of Illinois Counties. State of Illinois, March 2010.[1] Archived January 9, 2017, at theWayback Machine ^a b "Monthly Averages for Quincy, Illinois" . The Weather Channel.Archived from the original on October 23, 2012. RetrievedJanuary 27, 2011 .^ "Population, Housing Units, Area, and Density: 2010 - County" .United States Census Bureau . Archived fromthe original on February 12, 2020. RetrievedJuly 11, 2015 .^ "Population and Housing Unit Estimates Tables" . United States Census Bureau. RetrievedJuly 24, 2025 .^ "U.S. Decennial Census" . United States Census Bureau.Archived from the original on July 17, 2022. RetrievedJuly 3, 2014 .^ "Historical Census Browser" . University of Virginia Library.Archived from the original on May 30, 2019. RetrievedJuly 3, 2014 .^ "Population of Counties by Decennial Census: 1900 to 1990" . United States Census Bureau.Archived from the original on April 24, 2014. RetrievedJuly 3, 2014 .^ "Census 2000 PHC-T-4. Ranking Tables for Counties: 1990 and 2000" (PDF) . United States Census Bureau.Archived (PDF) from the original on December 18, 2014. RetrievedJuly 3, 2014 .^a b c "2020 Decennial Census Demographic Profile (DP1)" .United States Census Bureau . 2021. RetrievedDecember 25, 2025 .^ "2020 Decennial Census Redistricting Data (Public Law 94-171)" .United States Census Bureau . 2021. RetrievedDecember 25, 2025 .^ "2020 Decennial Census Demographic and Housing Characteristics (DHC)" .United States Census Bureau . 2023. RetrievedDecember 25, 2025 .^ "1980 Census of Population - General Population Characteristics - Illinois- Table 14 - Persons by Race and Table 16 (p. 18-28) - Total Persons and Spanish Origin Persons by Type of Spanish Origin and Race (p. 29-39)" (PDF) .United States Census Bureau ^ "1990 Census of Population - General Population Characteristics - Illinois - Table 6 - Race and Hispanic Orogin" (PDF) .United States Census Bureau ^ "P004: Hispanic or Latino, and Not Hispanic or Latino by Race – 2000: DEC Summary File 1 – Adams County, Illinois" .United States Census Bureau ^ "P2: Hispanic or Latino, and Not Hispanic or Latino by Race – 2010: DEC Redistricting Data (PL 94-171) – Adams County, Illinois" .United States Census Bureau ^ "P2: Hispanic or Latino, and Not Hispanic or Latino by Race – 2020: DEC Redistricting Data (PL 94-171) – Adams County, Illinois" .United States Census Bureau ^ included in the Asian category in the 1980 Census ^ included in the Asian category in the 1990 Census ^ not an option in the 1980 Census ^ not an option in the 1990 Census ^ "DP03 SELECTED ECONOMIC CHARACTERISTICS – 2006-2010 American Community Survey 5-Year Estimates" .United States Census Bureau . Archived fromthe original on February 13, 2020. RetrievedJuly 11, 2015 .^ Leip, David."Dave Leip's Atlas of U.S. Presidential Elections" .uselectionatlas.org .Archived from the original on March 23, 2018. RetrievedOctober 28, 2018 . ^ "Archived copy" . Archived fromthe original on February 13, 2012. RetrievedApril 29, 2009 .{{cite web }}: CS1 maint: archived copy as title (link )^ White, Jesse, ed. (2021). "Counties & County Officers".Illinois Blue Book 2021-2022 (PDF) .Springfield, Illinois :Illinois Secretary of State . Archived fromthe original (PDF) on April 4, 2023. RetrievedMay 23, 2023 . ^ Sorensen, Mike (December 1, 2022)."Three Adams County officials sworn in on Thursday" .Herald-Whig the original on December 2, 2022. RetrievedMay 23, 2023 . ^ Geography Division (December 22, 2020).2020 CENSUS - SCHOOL DISTRICT REFERENCE MAP: Adams County, IL (PDF) (Map).U.S. Census Bureau . RetrievedJune 2, 2025 . Text list ^ "Blessed Sacrament Catholic School – Quincy, Illinois – #beasaint" .www.blessedscs.org .Archived from the original on June 9, 2023. RetrievedJune 27, 2023 .^ "Chaddock | Treatment Services for Struggling Children | Quincy IL" . February 13, 2019.Archived from the original on June 27, 2023. RetrievedJune 27, 2023 .^ "St. Dominic School" .www.stdominicquincy.org .Archived from the original on June 8, 2023. RetrievedJune 27, 2023 .^ "Parish Home - St. Francis Solanus - Quincy, IL" .stfrancissolanus.com . November 3, 2018.Archived from the original on June 12, 2023. RetrievedJune 27, 2023 .^ "St James Lutheran Church and School Quincy, IL" . Archived fromthe original on August 3, 2009.^ "Home | St.Peter School" .stpeterschool.com . May 10, 2016.Archived from the original on May 15, 2023. RetrievedJune 27, 2023 .^ "Adams County Fair - Adams County Fair Home" . Archived fromthe original on June 21, 2009.^ "Burton Cave Nature Preserve Adams County" . Archived fromthe original on March 8, 2010. RetrievedJune 28, 2023 .^ "Welcome to the Prairie Mills Windmill, Golden Illinois" .www.goldenwindmill.org .Archived from the original on May 20, 2009. RetrievedJuly 8, 2009 .^ "Mississippi Valley Council, BSA Saukenauk Scout Reservation Information" . June 11, 2009. Archived fromthe original on June 11, 2009.^ "Spirit Knob Winery" . Archived fromthe original on July 26, 2009.^ "Let's make a profit through gambling" .Let's make a profit through gambling .Archived from the original on April 2, 2023. RetrievedJune 27, 2023 .^ "Quincy Parks and Facilities" . July 8, 2009. Archived fromthe original on July 8, 2009.
Places adjacent to Adams County, Illinois
International National Other
39°59′N 91°11′W / 39.99°N 91.19°W /39.99; -91.19
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