North Sioux City is a city in Union County, South Dakota, United States. The population was 2,530 at the 2010 census. It is part of the Sioux City, IA-NE-SD Metropolitan Statistical Area.
North Sioux City is located at 42°31′52″N 96°29′44″W / 42.53111°N 96.49556°W / 42.53111; -96.49556 (42.530999, -96.495494), bounded on the east by the Big Sioux River and on the west by the oxbow McCook Lake.
According to the United States Census Bureau, the city has a total area of 2.29 square miles (5.93 km), of which, 2.26 square miles (5.85 km) is land and 0.03 square miles (0.08 km) is water.
North Sioux City has been assigned the ZIP code 57049 and the FIPS place code 45700.
As of the census of 2010, there were 2,530 people, 1,073 households, and 679 families residing in the city. The population density was 1,119.5 inhabitants per square mile (432.2/km). There were 1,146 housing units at an average density of 507.1 per square mile (195.8/km). The racial makeup of the city was 93.5% White, 0.6% African American, 1.3% Native American, 0.6% Asian, 0.1% Pacific Islander, 1.4% from other races, and 2.6% from two or more races. Hispanic or Latino of any race were 3.8% of the population.
There were 1,073 households of which 31.5% had children under the age of 18 living with them, 46.3% were married couples living together, 12.0% had a female householder with no husband present, 4.9% had a male householder with no wife present, and 36.7% were non-families. 30.3% of all households were made up of individuals and 10.2% had someone living alone who was 65 years of age or older. The average household size was 2.36 and the average family size was 2.93.
The median age in the city was 37.4 years. 24.7% of residents were under the age of 18; 7.7% were between the ages of 18 and 24; 27% were from 25 to 44; 27.4% were from 45 to 64; and 13.1% were 65 years of age or older. The gender makeup of the city was 49.0% male and 51.0% female.
As of the census of 2000, there were 2,288 people, 916 households, and  621 families residing in the city. The population density was 1,021.7 people per square mile (394.4/km²). There were 953 housing units at an average density of 425.6 per square mile (164.3/km²). The racial makeup of the city was 95.32% White, 0.61% African American, 0.79% Native American, 1.05% Asian, 0.04% Pacific Islander, 0.57% from other races, and 1.62% from two or more races. Hispanic or Latino of any race were 2.49% of the population.
There were 916 households out of which 37.2% had children under the age of 18 living with them, 51.3% were married couples living together, 11.8% had a female householder with no husband present, and 32.1% were non-families. 25.0% of all households were made up of individuals and 7.9% had someone living alone who was 65 years of age or older. The average household size was 2.50 and the average family size was 2.99.
In the city, the population was spread out with 27.1% under the age of 18, 9.3% from 18 to 24, 32.3% from 25 to 44, 20.7% from 45 to 64, and 10.6% who were 65 years of age or older. The median age was 34 years. For every 100 females, there were 106.9 males. For every 100 females age 18 and over, there were 104.2 males.
As of 2000 the median income for a household in the city was $39,333, and the median income for a family was $44,926. Males had a median income of $31,800 versus $22,480 for females. The per capita income for the city was $21,416. About 5.0% of families and 5.7% of the population were below the poverty line, including 9.3% of those under age 18 and 3.7% of those age 65 or over.