| Official Name: | Loomis, South Dakota |
| Settlement Type: | CDP |
| Mapsize: | 250px |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | South Dakota |
| Subdivision Type2: | County |
| Subdivision Name2: | Davison |
| Unit Pref: | Imperial |
| Area Footnotes: | [1] |
| Area Total Km2: | 0.51 |
| Area Land Km2: | 0.51 |
| Area Water Km2: | 0.00 |
| Area Total Sq Mi: | 0.20 |
| Area Land Sq Mi: | 0.20 |
| Area Water Sq Mi: | 0.00 |
| Population As Of: | 2020 |
| Population Footnotes: | [2] |
| Population Total: | 33 |
| Population Density Km2: | 64.36 |
| Population Density Sq Mi: | 166.67 |
| Timezone: | Central (CST) |
| Utc Offset: | -6 |
| Timezone Dst: | CDT |
| Utc Offset Dst: | -5 |
| Coordinates: | 43.7931°N -98.1047°W |
| Elevation Ft: | 1303 |
| Postal Code Type: | ZIP code |
| Postal Code: | 57301 |
| Area Code: | 605 |
| Blank Name: | FIPS code |
| Blank Info: | 46-39020[3] |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 2393108 |
Loomis is a census-designated place (CDP) in Davison County, South Dakota, United States. The population was 33 at the 2020 census.[4] It is part of the Mitchell, South Dakota Micropolitan Statistical Area.
Loomis was laid out in 1902.[5]
According to the United States Census Bureau, the CDP has a total area of 0.2sqmi, all land.
As of the census of 2000, there were 47 people, 18 households, and 14 families residing in the CDP. The population density was 242.8sp=usNaNsp=us. There were 19 housing units at an average density of 98.1sp=usNaNsp=us. The racial makeup of the CDP was 97.87% White and 2.13% Native American.
There were 18 households, out of which 44.4% had children under the age of 18 living with them, 66.7% were married couples living together, 5.6% had a female householder with no husband present, and 22.2% were non-families. 16.7% of all households were made up of individuals, and 5.6% had someone living alone who was 65 years of age or older. The average household size was 2.61 and the average family size was 2.86.
In the CDP, the population was spread out, with 27.7% under the age of 18, 4.3% from 18 to 24, 31.9% from 25 to 44, 29.8% from 45 to 64, and 6.4% who were 65 years of age or older. The median age was 36 years. For every 100 females, there were 123.8 males. For every 100 females age 18 and over, there were 142.9 males.
The median income for a household in the CDP was $28,750, and the median income for a family was $28,750. Males had a median income of $28,750 versus $0 for females. The per capita income for the CDP was $13,123. None of the population or families were below the poverty line.