Richardson County is a county located in the U.S. state of Nebraska. As of the 2010 census, the population was 8,363. Its county seat is Falls City.
In the Nebraska license plate system, Richardson County is represented by the prefix 19 (it had the nineteenth-largest number of vehicles registered in the county when the license plate system was established in 1922).
Part of the Iowa Reservation of Kansas and Nebraska is located in the southeast corner of the county.
Richardson County was formed in 1855. It was named after William A. Richardson, a governor of the Nebraska Territory.
On May 30, 1879, the "Irving, Kansas Tornado" passed through Richardson County. This tornado measured F4 on the Fujita scale, and had a damage path 800 yards (730 m) wide and 100 miles (160 km) long. Eighteen people were killed and sixty were injured in this tornado.