Sidney is a city located in Shelby County Ohio. It is also the county seat of Shelby County. With a 2020 population of 20,365, it is the 82nd largest city in Ohio and the 1827th largest city in the United States . Sidney is currently declining at a rate of -0.21% annually and its population has decreased by -4.07% since the most recent census, which recorded a population of 21,229 in 2010. Sidney reached it's highest population of 21,159 in 2010. Spanning over 12 miles, Sidney has a population density of 1,701 people per square mile.
The average household income in Sidney is $65,144 with a poverty rate of 13.83%. The median rental costs in recent years comes to $697 per month, and the median house value is $111,100. The median age in Sidney is 37.1 years, 36.8 years for males, and 37.4 years for females.