| Brant Lake South, South Dakota | |
| Settlement Type: | Census-designated place |
| Pushpin Map: | South Dakota#USA |
| Pushpin Label: | Brant Lake South |
| Pushpin Map Caption: | Location in South Dakota##Location in the United States |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | South Dakota |
| Subdivision Type2: | County |
| Subdivision Name2: | Lake |
| Unit Pref: | Imperial |
| Area Footnotes: | [1] |
| Area Total Km2: | 2.67 |
| Area Land Km2: | 1.36 |
| Area Water Km2: | 1.31 |
| Population As Of: | 2020 |
| Population Footnotes: | [2] |
| Population Total: | 140 |
| Population Density Km2: | 102.93 |
| Timezone: | Central (CST) |
| Utc Offset: | -6 |
| Timezone Dst: | CDT |
| Utc Offset Dst: | -5 |
| Elevation Ft: | 1620 |
| Coordinates: | 43.9106°N -96.9364°W |
| Postal Code Type: | ZIP code |
| Blank Name: | FIPS code |
| Blank Info: | 46-07044 |
| Blank1 Name: | GNIS feature ID |
| Area Total Sq Mi: | 1.03 |
| Area Land Sq Mi: | 0.53 |
| Area Water Sq Mi: | 0.51 |
| Population Density Sq Mi: | 266.67 |
Brant Lake South is a census-designated place (CDP) in Lake County, South Dakota, United States. The population was 140 at the 2020 census.[3] It was established after the 2010 census.
Brant Lake South is in southeastern Lake County, on the south side of Brant Lake. It is bordered to the north by the town of Brant Lake and to the south by the unincorporated community of Chester. Madison, the county seat, is to the northwest.
According to the U.S. Census Bureau, the Brant Lake South CDP has an area of 2.7sqkm, of which 1.4sqkm are land and 1.3sqkm, comprising the southeastern portion of Brant Lake, are water.[4] Skunk Creek, the outlet of Brant Lake, passes through the southwest corner of the CDP and flows south to the Big Sioux River at Sioux Falls.