Bainbridge Island, WA has a population of 23,576 and is the 1,849th largest city in the United States. The population density is 854 per sq mi which is 783% higher than the Washington average and 842% higher than the national average. The median age in Bainbridge Island is 49 which is approximately 29% higher than the Washington average of 38. In Bainbridge Island, 69% of the population over 15 years of age are married, 95% speak English and 1% speak Spanish. 32% of Bainbridge Island residents were born in Washington, 58% were born out of state, 2% were born outside of the United States and 7% were foreign born.