At the 2000 census, there were 1,321 people, 543 households and 349 families residing in the town. The population density was . There were 689 housing units at an average density of . The racial makeup of the town was 97.43% White, 0.38% African American, 0.61% Native American, 0.23% Asian, 0.61% from other races, and 0.76% from two or more races. Hispanic or Latino of any race were 1.14% of the population.
There were 543 households, of which 32.4% had children under the age of 18 living with them, 55.1% were married couples living together, 7.7% had a female householder with no husband present, and 35.7% were non-families. 28.2% of all households were made up of individuals, and 13.4% had someone living alone who was 65 years of age or older. The average household size was 2.43 and the average family size was 3.04.
Age distribution was 25.8% under the age of 18, 6.3% from 18 to 24, 29.1% from 25 to 44, 26.6% from 45 to 64, and 12.3% who were 65 years of age or older. The median age was 39 years. For every 100 females, there were 98.1 males. For every 100 females age 18 and over, there were 90.7 males.
The median household income was $39,500, and the median family income was $51,250. Males had a median income of $36,696 versus $23,828 for females. The per capita income for the town was $18,828. About 4.0% of families and 8.1% of the population were below the poverty line, including 9.6% of those under age 18 and 11.0% of those age 65 or over.
Communities and locations in St. Armand
- Bloomingdale – A hamlet near the northern town line on NY-3. The community was founded circa 1852.
- Camp Woodsmoke – A youth camp formerly located at the northern end of Lake Placid.
- Franklin Falls Pond – A wide part of the Saranac River at the northern town boundary.
- Lake Placid – A small part of the northern end of the lake is within the town.
- Moose Pond – A small lake in the western part of St. Armand.
- Saranac Lake – A small part of the village of Saranac Lake is in the southwestern part of the town.
- St. Armand – A location near the northern town line on NY-3.
- Trudeau – A hamlet northeast of Saranac Lake village on NY-3, named for Dr. Edward Livingston Trudeau.