Plainfield is a village in Will and Kendall counties, Illinois, United States. The population was 39,581 at the 2010 census and an estimated 43,926 in 2017.
Plainfield is located in northwestern Will County at 41°37′2″N 88°12′10″W / 41.61722°N 88.20278°W / 41.61722; -88.20278 (41.617280, -88.202837). The village limits extend west into the eastern part of Kendall County. Plainfield is bordered to the north by the city of Naperville, to the northeast by the village of Bolingbrook, to the east by the village of Romeoville, and to the south by the city of Joliet. Farmland in Kendall County is to the west.
Interstate 55 runs along the eastern edge of the village, with access from two exits. I-55 leads northeast 34 miles (55 km) to the center of Chicago and southwest 100 miles (160 km) to Bloomington. U.S. Route 30 passes through the center of Plainfield, leading northwest 13 miles (21 km) to Montgomery and southeast 9 miles (14 km) to Joliet. Illinois Route 126 crosses US-30 in the center of Plainfield, leading northeast 2.5 miles (4.0 km) to I-55 and west 14 miles (23 km) to Yorkville. Illinois Route 59 runs through the center of Plainfield with US-30 but leads north 9 miles (14 km) to the west side of Naperville and south 6 miles (10 km) to Shorewood.
According to the 2010 census, Plainfield has a total area of 24.199 square miles (62.68 km), of which 23.22 square miles (60.14 km) (or 95.95%) is land and 0.979 square miles (2.54 km) (or 4.05%) is water. The DuPage River flows through the village center, running south towards the Des Plaines River in the Illinois River watershed.
Like its namesake, Plainfield’s topography is generally flat. Thousands of years ago, land in greater Plainfield used to be part of the bed of proglacial Lake Wauponsee. However, the lake did not hold up long, and eventually drained into the Illinois River valley. The lake left behind a very flat landscape. Much of downtown Plainfield has an elevation of around 600–625 feet (183–191 m) above sea level, with some areas in the western and northwestern portions of the village’s outskirts exceeding 700 feet (210 m). This rise in elevation was created by terminal moraines that were formed during the Wisconsin Episode of the last ice age’s last glacial period that has been recorded.
As of the census of 2010, there were 39,581 people, 11,920 households, and 10,155 families residing in the village. The population density was 1,621.5 people per square mile (626/km²). There were 12,532 housing units at an average density of 513.4 per square mile (198.2/km²). The racial makeup of the village was 81.72% White, 5.56% African American, 0.22% Native American, 7.62% Asian, 0.04% Pacific Islander, 2.6% from other races, and 2.22% from two or more races. Hispanic or Latino of any race were 10.73% of the population.
There were 11,920 households out of which 55.4% had children under the age of 18 living with them, 74.2% were married couples living together, 7.9% had a female householder with no husband present, and 14.8% were non-families. 11.5% of all households were made up of individuals and 2.9% had someone living alone who was 65 years of age or older. The average household size was 3.31 and the average family size was 3.62.
In the village, the population was spread out with 35.2% under the age of 18, 6% from 18 to 24, 31.8% from 25 to 44, 21.7% from 45 to 64, and 5.3% who were 65 years of age or older. The median age was 33.8 years. For every 100 females, there were 98.4 males. For every 100 females age 18 and over, there were 95 males.
According to a 2014 estimate by the U.S. Census, the median income for a household in the village was $111,536. About 1.0% of families and 1.8% of the population were below the poverty line, including 2.2% of those under age 18 and 2.3% of those age 65 or over.
In Plainfield, Illinois the crime is problematic. Only 23% of residents report feeling ‘very safe’. The most common crimes in Plainfield are theft, assault, and burglary in order of prevalence.