Zillah is a city located in Washington. With a 2020 population of 3,136, it is the 142nd largest city in Washington and the 6117th largest city in the United States. Zillah is currently declining at a rate of -0.06% annually but its population has increased by 5.80% since the most recent census, which recorded a population of 2,964 in 2010. Zillah reached it's highest population of 3,142 in 2018. Spanning over 2 miles, Zillah has a population density of 1,726 people per square mile.
The average household income in Zillah is $72,247 with a poverty rate of 16.05%. The median rental costs in recent years comes to $921 per month, and the median house value is $178,400. The median age in Zillah is 39.4 years, 39.8 years for males, and 37.2 years for females. For every 100 females there are 107.6 males.