St. Francis is a city in Clay County, Arkansas, United States, along the St. Francis River. The population was 250 at the 2010 census.
St. Francis is located at near the northeastern corner of Clay County 36°27′13″N 90°8′36″W / 36.45361°N 90.14333°W / 36.45361; -90.14333 (36.453583, -90.143251). It is bordered on the east by the St. Francis River, which forms the Arkansas–Missouri state line. U.S. Route 62 passes through the community, leading south and west 7 miles (11 km) to Piggott, and northeast 4 miles (6 km) to Campbell, Missouri.
According to the United States Census Bureau, St. Francis has a total area of 0.37 square miles (0.95 km), all land.
As of the census of 2000, there were 250 people, 103 households, and 70 families residing in the city. The population density was 837.1 people per square mile (321.8/km²). There were 125 housing units at an average density of 418.5/sq mi (160.9/km²). The racial makeup of the city was 96.80% White, 1.20% Native American, and 2.00% from two or more races. 0.40% of the population were Hispanic or Latino of any race.
There were 103 households out of which 34.0% had children under the age of 18 living with them, 55.3% were married couples living together, 10.7% had a female householder with no husband present, and 31.1% were non-families. 27.2% of all households were made up of individuals and 13.6% 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 2.94.
In the city, the population was spread out with 25.6% under the age of 18, 12.0% from 18 to 24, 28.0% from 25 to 44, 21.6% from 45 to 64, and 12.8% who were 65 years of age or older. The median age was 33 years. For every 100 females, there were 95.3 males. For every 100 females age 18 and over, there were 91.8 males.
The median income for a household in the city was $30,278, and the median income for a family was $33,250. Males had a median income of $19,205 versus $13,563 for females. The per capita income for the city was $11,198. About 16.9% of families and 20.2% of the population were below the poverty line, including 25.0% of those under the age of eighteen and 38.2% of those sixty five or over.