Lemmon, SD has a population of 1,362 and is the 13,262nd largest city in the United States. The population density is 1,313 per sq mi which is 12042% higher than the South Dakota average and 1349% higher than the national average. The median age in Lemmon is 49 which is approximately 33% higher than the South Dakota average of 37. In Lemmon, 64% of the population over 15 years of age are married, 96% speak English and 2% speak Spanish. 43% of Lemmon residents were born in South Dakota, 55% were born out of state, 1% were born outside of the United States and 1% were foreign born.