St. Regis, MT has a population of 207 and is the 24,308th largest city in the United States. The population density is 242 per sq mi which is 3439% higher than the Montana average and 167% higher than the national average. The median age in St. Regis is 39 which is approximately 3% lower than the Montana average of 40. In St. Regis, 50% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 40% of St. Regis residents were born in Montana, 60% were born out of state, 0% were born outside of the United States and 0% were foreign born.