| Official Name: | Foster, Indiana |
| Settlement Type: | Unincorporated community and Census-designated place |
| Pushpin Map: | USA Indiana Warren County#Indiana#USA |
| Pushpin Label: | Foster |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Indiana |
| Subdivision Type2: | County |
| Subdivision Name2: | Warren |
| Subdivision Type3: | Township |
| Subdivision Name3: | Mound |
| Established Title: | Founded |
| Established Date: | 1893 |
| Named For: | William R. Foster |
| Area Total Km2: | 3.33 |
| Area Land Km2: | 3.33 |
| Population As Of: | 2020 |
| Population Total: | 104 |
| Population Density Km2: | 31.24 |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Coordinates: | 40.1417°N -87.4686°W |
| Elevation Ft: | 630 |
| Postal Code Type: | ZIP code |
| Postal Code: | 47993 |
| Area Code: | 765 |
| Blank Name: | GNIS feature ID |
| Blank Info: | 2806489 |
| Unit Pref: | Imperial |
| Area Footnotes: | [1] |
| Area Total Sq Mi: | 1.29 |
| Area Water Km2: | 0.00 |
| Area Land Sq Mi: | 1.29 |
| Area Water Sq Mi: | 0.00 |
| Population Density Sq Mi: | 80.87 |
Foster is a small unincorporated community in Mound Township, Warren County, in the U.S. state of Indiana.
Foster was platted April 25, 1893 on land donated by William R. Foster, an early settler.[2] At one time the town had a post office, blacksmith shop, railroad depot, two stores, a stockyard, a threshing machine, a grain elevator and a sawmill.[3] Currently it consists of a few private residences, a couple of small shops and a motel.
A post office was established at Foster in 1883, and remained in operation until it was discontinued in 1905.[4]
Foster is located just north of U.S. Route 136 about west of Covington and about east of the Indiana-Illinois border. The Vermilion Valley Railroad (originally the New York Central Railroad) passes through Fowler, and the north fork of Spring Creek flows along its western edge.[5]