Eureka is a city located in Greenwood County Kansas. It is also the county seat of Greenwood County. With a 2020 population of 2,318, it is the 103rd largest city in Kansas and the 7093rd largest city in the United States . Eureka is currently declining at a rate of -0.60% annually and its population has decreased by -11.96% since the most recent census, which recorded a population of 2,633 in 2010. Eureka reached it's highest population of 4,055 in 1960. Spanning over 2 miles, Eureka has a population density of 1,012 people per square mile.
The average household income in Eureka is $46,347 with a poverty rate of 20.31%. The median rental costs in recent years comes to $552 per month, and the median house value is $49,800. The median age in Eureka is 43.3 years, 38 years for males, and 49.8 years for females.