Quincy, Illinois

Quincy population, 2020 to 2024

Quincy lost 789 residents from July 2020 to July 2024, a change of -2.0%. In the latest year it moved by -173. Among 330 Illinois places of 5,000 or more, that growth ranks 220th; the median place changed by -0.9%. The median place of 5,000+ in Illinois has 14,760 people, so Quincy is 2.6 times that size.

Quincy covers 15.92 square miles of land and 0.04 of water, for 2,436 people per square mile of land. The median Illinois place of 5,000+ has 2,177, so Quincy is denser than the typical town.

What county Quincy is in

All of Quincy's residents live in Adams County, which had 64,109 residents in 2024. Quincy holds 60.5% of the county's population. The shaded shape is on the map above; dots mark the eight nearest places.

ZIP codes in Quincy

2 ZIP Code Tabulation Areas (ZCTAs) overlap Quincy by at least 10% of the ZCTA's or the city's land: 62301, 62305. ZCTAs are Census approximations of USPS ZIP code delivery areas. The list comes from the 2020 ZCTA to place relationship file, so a city that annexed land after 2020 may reach into ZIP codes not listed here.

Where Quincy is

The Census internal point of Quincy is at 39.933700, -91.379300. Springfield, the capital, is 92.3 miles E in a straight line. The nearest larger place is Wentzville, MO (48,646 people), 81.8 miles away. The nearest city of 100,000 or more is Columbia, MO, 84.8 miles away.

Daylight in Quincy

At 39.93° N, Quincy gets about 15 h 01 min of daylight around the June solstice and 9 h 20 min around the December solstice, a swing of 5 h 40 min. Figures are sunrise to sunset from the SunCalc model for June 21 and December 21, 2026.

Places near Quincy

The eight nearest incorporated places of 1,000+ in Illinois, measured between internal points. The closest is Camp Point, 18.1 miles away, with 1,117 people.