St. John is a city located in Washington. With a 2020 population of 543, it is the 234th largest city in Washington and the 12966th largest city in the United States. St. John is currently declining at a rate of -1.45% annually but its population has increased by 1.12% since the most recent census, which recorded a population of 537 in 2010. St. John reached it's highest population of 568 in 2017. Spanning over 1 miles, St. John has a population density of 810 people per square mile.
The average household income in St. John is $59,333 with a poverty rate of 11.96%. The median rental costs in recent years comes to $648 per month, and the median house value is $131,500. The median age in St. John is 52.2 years, 53.3 years for males, and 50.4 years for females. For every 100 females there are 90.0 males.