Fort Sumner, NM has a population of 1,243 and is the 13,824th largest city in the United States. The population density is 375 per sq mi which is 2088% higher than the New Mexico average and 314% higher than the national average. The median age in Fort Sumner is 54 which is approximately 45% higher than the New Mexico average of 37. In Fort Sumner, 32% of the population over 15 years of age are married, 56% speak English and 44% speak Spanish. 79% of Fort Sumner residents were born in New Mexico, 19% were born out of state, 0% were born outside of the United States and 2% were foreign born.