Black Diamond is a city located in Washington. With a 2020 population of 5,467, it is the 120th largest city in Washington and the 4527th largest city in the United States. Black Diamond is currently growing at a rate of 6.69% annually and its population has increased by 31.70% since the most recent census, which recorded a population of 4,151 in 2010. Black Diamond reached it's highest population of 5,467 in 2021. Spanning over 7 miles, Black Diamond has a population density of 835 people per square mile.
The average household income in Black Diamond is $124,201 with a poverty rate of 4.94%. The median rental costs in recent years comes to $1,065 per month, and the median house value is $413,100. The median age in Black Diamond is 42 years, 41.5 years for males, and 42.2 years for females. For every 100 females there are 97.5 males.