Dallas County is a county located in the U.S. state of Arkansas. As of the 2020 census, the population was 6,482, making it the fourth-least populous county in Arkansas. The county seat is Fordyce. Dallas County is Arkansas's 49th county, formed on January 1, 1845; it was named for George M. Dallas, 11th Vice President of the United States.

Fordyce is a city in southeast Dallas County, Arkansas, United States. Its population has been decreasing since the 1980s when the town reached an all time high of 5,175. The population in 2020 was 3,396 down from 4,300 at the 2010 census, and from 4,799 in 2000.