| Official Name: | Union Township |
| Settlement Type: | Township |
| Subdivision Type: | Country |
| Subdivision Type1: | State |
| Subdivision Type2: | County |
| Subdivision Name2: | St. Joseph |
| Government Type: | Indiana township |
| Area Total Km2: | 111.62 |
| Area Land Km2: | 111.08 |
| Area Water Km2: | 0.54 |
| Unit Pref: | Imperial |
| Area Total Sq Mi: | 43.1 |
| Area Land Sq Mi: | 42.89 |
| Area Water Sq Mi: | 0.21 |
| Area Water Percent: | 0.48 |
| Population As Of: | 2020 |
| Population Footnotes: | [1] |
| Population Total: | 3478 |
| Population Density Km2: | 29.6 |
| Population Density Sq Mi: | 76.7 |
| Elevation Footnotes: | [2] |
| Elevation M: | 258 |
| Elevation Ft: | 846 |
| Coordinates: | 41.5189°N -86.2611°W |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Postal Code Type: | ZIP codes |
| Postal Code: | 46506, 46536, 46554, 46614 |
| Area Code: | 574 |
| Blank Name: | GNIS feature ID |
| Blank Info: | 453933 |
Union Township is one of thirteen townships in St. Joseph County, in the U.S. state of Indiana.[3] As of the 2000 census, its population was 3,289.[4]
According to the United States Census Bureau, Union Township covers an area of ; of this, (99.52 percent) is land and (0.48 percent) is water.
(This list is based on USGS data and may include former settlements.)
The township contains Lakeville Cemetery.