Alsea, OR has a population of 283 and is the 22,796th largest city in the United States. The population density is 1,833 per sq mi which is 4530% higher than the Oregon average and 1924% higher than the national average. The median age in Alsea is 29 which is approximately 26% lower than the Oregon average of 39. In Alsea, 57% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 86% of Alsea residents were born in Oregon, 14% were born out of state, 0% were born outside of the United States and 0% were foreign born.