Southwest Harbor, ME has a population of 850 and is the 16,186th largest city in the United States. The population density is 631 per sq mi which is 1580% higher than the Maine average and 597% higher than the national average. The median age in Southwest Harbor is 49 which is approximately 10% higher than the Maine average of 44. In Southwest Harbor, 55% of the population over 15 years of age are married, 98% speak English and 0% speak Spanish. 32% of Southwest Harbor residents were born in Maine, 58% were born out of state, 4% were born outside of the United States and 7% were foreign born.