Smithland is one of the oldest settlements in Woodbury County. In 1857, clashes between settlers and Indians began at what is now Smithland which would afterward culminate in the Spirit Lake Massacre.
At the 2010 census, there were 224 people, 100 households and 65 families living in the city. The population density was. There were 109 housing units at an average density of. The racial makeup of the city was 97.3% White, 2.2% from other races, and 0.4% from two or more races. Hispanic or Latino of any race were 3.1% of the population. There were 100 households of which 23.0% had children under the age of 18 living with them, 44.0% were married couplesliving together, 13.0% had a female householder with no husband present, 8.0% had a male householder with no wife present, and 35.0% were non-families. 32.0% of all households were made up of individuals and 21% had someone living alone who was 65 years of age or older. The average household size was 2.24 and the average family size was 2.66. The median age was 49 years. 19.6% of residents were under the age of 18; 7.2% were between the ages of 18 and 24; 19.7% were from 25 to 44; 28.6% were from 45 to 64; and 25% were 65 years of age or older. The gender makeup of the city was 50.4% male and 49.6% female.
At the 2000 census, there were 221 people, 101 households and 72 families living in the city. The population density was 613.0 per square mile. There were 114 housing units at an average density of 316.2 per square mile. The racial makeup of the city was 99.10% White, 0.45% Native American, and 0.45% from two or more races. Hispanic or Latino of any race were 0.45% of the population. There were 101 households of which 19.8% had children under the age of 18 living with them, 56.4% were married couples living together, 8.9% had a female householder with no husband present, and 28.7% were non-families. 27.7% of all households were made up of individuals and 15.8% had someone living alone who was 65 years of age or older. The average household size was 2.19 and the average family size was 2.60. 19.0% of the population were under the age of 18, 7.2% from 18 to 24, 17.2% from 25 to 44, 29.4% from 45 to 64, and 27.1% who were 65 years of age or older. The median age was 49 years. For every 100 females, there were 100.9 males. For every 100 females age 18 and over, there were 90.4 males. The median household income was $31,406 and the median family income was $33,750. Males had a median income of $31,250 and females $17,188. The per capita income was $14,722. About 4.0% of families and 6.4% of the population were below the poverty line, including 7.0% of those under the age of eighteen and none of those sixty five or over.
