Culdesac is a city in Nez Perce County, Idaho, United States. The population was 380 at the 2010 census. It is part of the Lewiston, ID-WA Metropolitan Statistical Area.
Culdesac was named from its location at the end of a railroad line, i.e., a cul de sac.
Culdesac is located at 46°22′30″N 116°40′13″W (46.374883, -116.670333), at an elevation of 1,644 feet (501 m) above sea level.
According to the United States Census Bureau, the city has a total area of 0.23 square miles (0.60 km2), all of it land.
At the 2010 census there were 380 people in 156 households, including 106 families, in the city. The population density was 1,652.2 inhabitants per square mile (637.9/km2). There were 176 housing units at an average density of 765.2 per square mile (295.4/km2). The racial makup of the city was 83.4% White, 15.8% Native American, 0.3% from other races, and 0.5% from two or more races. Hispanic or Latino of any race were 5.3%.
Of the 156 households 32.7% had children under the age of 18 living with them, 43.6% were married couples living together, 14.7% had a female householder with no husband present, 9.6% had a male householder with no wife present, and 32.1% were non-families. 25.0% of households were one person and 11.5% were one person aged 65 or older. The average household size was 2.44 and the average family size was 2.85.