As of the census of 2000, there were 4,877 people, 1,654 households, and 1,374 families residing in the village. This figure does not include surrounding subdivisions which would almost double the population. The population density was 711.6 people per square mile (274.9/km²). There were 1,700 housing units at an average density of 248.0/sq mi (95.8/km²). The racial makeup of the village was 98.18% White, 0.14% African American, 0.10% Native American, 0.59% Asian, 0.39% from other races, and 0.59% from two or more races. Hispanic or Latino of any race were 0.94% of the population.
There were 1,654 households out of which 51.3% had children under the age of 18 living with them, 70.9% were married couples living together, 9.4% had a female householder with no husband present, and 16.9% were non-families. 14.1% of all households were made up of individuals and 6.0% had someone living alone who was 65 years of age or older. The average household size was 2.95 and the average family size was 3.27.
In the village the population was spread out with 34.3% under the age of 18, 6.4% from 18 to 24, 31.8% from 25 to 44, 20.6% from 45 to 64, and 6.9% who were 65 years of age or older. The median age was 34 years. For every 100 females there were 93.4 males. For every 100 females age 18 and over, there were 88.0 males.
The median income for a household in the village was $57,574, and the median income for a family was $61,063. Males had a median income of $46,277 versus $30,956 for females. The per capita income for the village was $21,990. About 3.5% of families and 5.1% of the population were below the poverty line, including 5.1% of those under age 18 and 3.9% of those age 65 or over.
The most popular tourist attractions in Mahomet are Lake of the Woods Park, River Bend Forest Preserve, and the award winning Hartwell C. Howard Golf Course. Lake of the Woods Park is a 900 acre (3.6 km²) park along the Sangamon River. The park features a botanical garden, a lake, and also offers activities like boating, fishing, cross country skiing, and sledding. Within Lake of the Woods Park is the Early American Museum, which has a collection that features life in the 19th and early 20th century in East-Central Illinois. The park has a bike path and a bell tower. The Hartwell C. Howard Golf Course is an 18 hole regulation course, a 9 hole par 3 course, and a practice range. The River Bend Forest Preserve is 275 acres (1.1 km²), of which 130 acres (0.5 km²) is water. The park has two large lakes, one of them being the largest lake in Champaign County and of forest along the Sangamon River.
The Mahomet School District has 2,678 students in grades K-12, 185 instructors and 10 administrators, spread over five schools. The school colors are orange and blue and the school mascot is a bulldog.
The village of Mahomet was first settled in 1832 on the banks of the Sangamon River. It was the first community to be established in modern day Champaign County. The original village name was Middletown, because it was half-way between the towns of Danville and Bloomington. In 1871, the name of the village was changed to Mahomet because there was already another Middletown in Illinois, which was causing mail problems. Most early settlers came from Ohio, Virginia, Kentucky, and Pennsylvania and chose to reside in Mahomet because there was abundant water from the Sangamon River and abundant trees. Currently, most residents commute to the city of Champaign to work, although the village has a thriving small business district.
The Illinois town's name derives from the "Mahomet Lodge," the local Masonic Lodge at the time the town was searching for a new name. Its use as the name of the lodge was a manifestation of the Freemasons' liberal use of religious names and stone mason tools and symbols. An alternative theory states that the name Mahomet was arbitrarily assigned when the conflicting names were noted by the US Postal Service.
Although the unusual spelling sometimes confuses newcomers, the pronunciation of Mahomet is muh-HOMM-it.