Newellton is a town in northern Tensas Parish in the northeastern part of the U.S. state of Louisiana. The population is 1,227 in the 2010 census, a decline of 255 persons, or 17 percent, from the 2000 tabulation of 1,482. Newellton in 2010 was 51 percent African American; in earlier census reports it had been 60 to 65 percent black. The average age of the population there is 41 years.