| Official Name: | Neponset Township |
| Settlement Type: | Township |
| Image Map1: | Map of Illinois highlighting Bureau County.svg |
| Mapsize1: | 150px |
| Map Caption1: | Bureau County's location in Illinois |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Illinois |
| Subdivision Type2: | County |
| Subdivision Name2: | Bureau |
| Established Title: | Established |
| Established Date: | November 6, 1849 |
| Area Total Sq Mi: | 36.15 |
| Area Land Sq Mi: | 36.14 |
| Area Water Sq Mi: | 0.01 |
| Area Water Percent: | 0.03 |
| Population As Of: | 2020 |
| Population Total: | 658 |
| Population Density Sq Mi: | auto |
| Elevation M: | 239 |
| Elevation Ft: | 784 |
| Coordinates: | 41.2803°N -89.7944°W |
| Timezone: | CST |
| Utc Offset: | -6 |
| Timezone Dst: | CDT |
| Utc Offset Dst: | -5 |
| Postal Code Type: | ZIP codes |
| Postal Code: | 61314, 61345 |
| Blank Name: | FIPS code |
| Blank Info: | 17-011-52012 |
| Unit Pref: | Imperial |
Neponset Township is one of twenty-five townships in Bureau County, Illinois, USA. As of the 2020 census, its population was 658 and it contained 313 housing units.[1] Neponset Township changed its name from Brawby Township on 5 March 1866.
According to the 2010 census, the township has a total area of, of which (or 99.97%) is land and (or 0.03%) is water.[1]
The southern and eastern parts of the township form part of the Illinois River watershed, the headwaters of Spoon River arising in the northeast portion of the township. The northwest portion of Neponset township is drained by Mud Creek, which flows into Green River, thence into Rock River.
As of the 2020 census[2] there were 658 people, 277 households, and 220 families residing in the township. The population density was 18.18PD/sqmi. There were 313 housing units at an average density of 8.65/sqmi. The racial makeup of the township was 90.58% White, 1.06% African American, 0.15% Native American, 0.76% Asian, 0.00% Pacific Islander, 2.74% from other races, and 4.71% from two or more races. Hispanic or Latino of any race were 4.71% of the population.
There were 277 households, out of which 18.80% had children under the age of 18 living with them, 70.76% were married couples living together, 2.53% had a female householder with no spouse present, and 20.58% were non-families. 16.20% of all households were made up of individuals, and 8.30% had someone living alone who was 65 years of age or older. The average household size was 2.35 and the average family size was 2.57.
The township's age distribution consisted of 15.8% under the age of 18, 4.9% from 18 to 24, 21.7% from 25 to 44, 35.2% from 45 to 64, and 22.4% who were 65 years of age or older. The median age was 54.1 years. For every 100 females, there were 109.3 males. For every 100 females age 18 and over, there were 100.7 males.
The median income for a household in the township was $93,281, and the median income for a family was $98,958. Males had a median income of $55,333 versus $33,125 for females. The per capita income for the township was $42,778. About 4.1% of families and 13.1% of the population were below the poverty line, including 26.2% of those under age 18 and 5.5% of those age 65 or over.