They were named after a fire engine. The name "REO Speedwagon" refers to Ransom Eli Olds, the founder of Oldsmobile. He also owned the The REO Motor Truck Company, which made a model in 1915 called the Speedwagon, a forerunner to the pickup truck.

Keyboard player Neal Doughty came up with the name. They are from Champaign,Illinois and there is a street named "REO Speedwagon Way."