| Official Name: | Square Lake, Maine |
| Settlement Type: | Unorganized territory |
| Mapsize: | 250px |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Maine |
| Subdivision Type2: | County |
| Subdivision Name2: | Aroostook |
| Unit Pref: | Imperial |
| Area Total Km2: | 1073.3 |
| Area Land Km2: | 991.5 |
| Area Water Km2: | 81.8 |
| Area Total Sq Mi: | 414.4 |
| Area Land Sq Mi: | 382.8 |
| Area Water Sq Mi: | 31.6 |
| Population As Of: | 2020 |
| Population Total: | 706 |
| Population Density Km2: | auto |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Elevation M: | 176 |
| Elevation Ft: | 577 |
| Coordinates: | 46.9961°N -68.3564°W |
| Postal Code Type: | ZIP code |
| Postal Code: | 04779 |
| Area Code: | 207 |
| Blank Name: | FIPS code |
| Blank Info: | 23-73472 |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 582742 |
Square Lake is an unorganized territory in Aroostook County, Maine, United States. The population was 706 at the 2020 census.[1]
According to the United States Census Bureau, the unorganized territory has a total area of 1073.3sqkm, of which 991.5sqkm is land and 81.8sqkm, or 7.63%, is water.[2] There are several lakes in the unorganized territory, including the eponymous Square Lake as well as Eagle Lake, Cross Lake, and Mud Lake.
There are 10 townships within the unorganized territory, plus one (T14R6 WELS) that is shared with Northwest Aroostook.
As of the 2000 census,[3] there were 615 people, 277 households, and 193 families living in the unorganized territory. The population density was 1.6 people per square mile (0.6/km2). There were 1,086 housing units, at an average density of 2.8sp=usNaNsp=us. The racial makeup was 99.51% White and 0.49% from two or more races.
There were 277 households, of which 19.5% had children under the age of 18 living with them, 62.5% were married couples living together, 4.3% had a female householder with no husband present, and 30.0% were non-families. In the unorganized territory, 24.5% of all households were made up of individuals, and 10.1% had someone living alone who was 65 years of age or older. The average household size was 2.22, and the average family size was 2.61.
In the unorganized territory, 17.4% of the population were under the age of 18, 4.2% were 18 to 24, 17.4% were 25 to 44, 40.0% were 45 to 64, and 21.0% were 65 or older. The median age was 50 years. For every 100 females, there were 106.4 males. For every 100 females age 18 and over, there were 104.0 males.
The median income for a household in the unorganized territory was $27,692, and the median income for a family was $31,250. Males had a median income of $33,333, versus $22,500 for females. The per capita income for the unorganized territory was $17,595. About 10.3% of families and 16.2% of the population were below the poverty line, including 27.9% of those under age 18 and 13.7% of those age 65 or over.