Grannis is a town in Polk County, Arkansas, United States. The population was 554 at the 2010 census.Near Grannis is the Boggs Springs Youth Encampment of the American Baptist Association, a retreat of Missionary Baptist churches.Grannis is located at 34°14′20″N 94°19′42″W / 34.23889°N 94.32833°W / 34.23889; -94.32833.According to the United States Census Bureau, the city has a total area of 8.6 square miles, all of it land.As of the census of 2000, there were 575 people, 210 households, and 164 families residing in the city. The population density was 66.6 people per square mile. There were 254 housing units at an average density of 29.4/sq mi. The racial makeup of the city was 78.78% White, 0.52% Black or African American, 4.35% Native American, 0.17% Pacific Islander, 14.09% from other races, and 2.09% from two or more races. 16.52% of the population were Hispanic or Latino of any race.There were 210 households out of which 37.