Millstone, KY has a population of 44 and is the 28,209th largest city in the United States. The population density is 206 per sq mi which is 87% higher than the Kentucky average and 127% higher than the national average. The median age in Millstone is 53 which is approximately 39% higher than the Kentucky average of 38. In Millstone, 55% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 80% of Millstone residents were born in Kentucky, 20% were born out of state, 0% were born outside of the United States and 0% were foreign born.