5) Mercer Island
Some people prefer larger suburbs over small towns, and Washington is home to wealthy neighborhoods of both types. Mercer Island has a sizable population of over 24,000, according to Niche. The per capita income is a nice $75,644. As such, you will have a consistent measure of financial comfort if you settle here. Mercer Island residents tend to largely vote Democrat rather than Republican, according to City-Data. This source also reports that most residents of King County consider themselves to not practice a religion. Therefore, this may not be the ideal home for highly conservative and religious folks. The largest age demographic is 65 and older, though, according to Niche, all age ranges are represented here. Niche also reports that the gender ratio is 51:49 female to male, and over 40% of residents have a bachelor’s degree.