| Official Name: | St. John Township |
| Settlement Type: | Township |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Indiana |
| Subdivision Type2: | County |
| Subdivision Name2: | Lake |
| Government Type: | Indiana township |
| Established Title: | founded |
| Established Date: | 1848 |
| Area Total Sq Mi: | 39.37 |
| Area Land Sq Mi: | 39.2 |
| Area Water Sq Mi: | 0.17 |
| Population As Of: | 2020 |
| Population Footnotes: | [1] |
| Population Total: | 68972 |
| Population Density Sq Mi: | 1702.6 |
| Elevation Footnotes: | [2] |
| Elevation M: | 207 |
| Elevation Ft: | 679 |
| Coordinates: | 41.4767°N -87.4625°W |
| Blank Name: | FIPS code |
| Blank Info: | 18-66870[3] |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 453819 |
St. John Township is one of eleven townships in Lake County, Indiana. As of the 2010 census, its population was 66,741 and it contained 25,691 housing units.[4]
St. John Township was established in 1848. It was named for John Hack, the first German settler.[5]
According to the 2010 census, the township has a total area of, of which (or 99.57%) is land and (or 0.43%) is water.[4]
The township includes the towns of Dyer, Schererville and St. John as well as the unincorporated areas of these towns.[6]
Zip codes in the township include 46307, 46311, 46319, 46373, and 46375. The State House districts are IN-11 and IN-15, and the State Senate districts are IN-1, IN-6, and a small portion of IN-2.[7]
The racial makeup of the township is 82.1% non-Hispanic White, 11.3% Hispanic, 2.73% African American, 2.23% Asian, 0.58% from other races, and 1.13% from two or more races. The percentages of Hispanic and African American residents are, respectively, 5.4 and 22.6 percent lower than Lake County as a whole.
Native-born citizens make up 91.9% of the population. Naturalized citizens are 5.3% of the population, while 1.9% are not citizens. The top ten countries of birth for foreign-born residents are Mexico, India, Croatia, Poland, Serbia, Greece, Macedonia, Philippines, Germany, and Bosnia and Herzegovina. The most common self-reported ancestries are: German (23.1%), Polish (17%), Irish (15.9%), Mexican (8.72%), Unclassified/Unreported (8.5%), Italian (8.1%), English (7.3%), Dutch (5.6%), American (4.7%), and Serbian (2.8%).