The Insco Apartments is a historic apartment building in downtown Dayton, Ohio, United States. It was designed by Charles Insco Williams, a native of Dayton, and constructed in 1894. Williams designed the structure after an apartment hotel that he had seen on Fifth Avenue in New York City; he did not copy the design slavishly, but many of the architectural themes present in the Insco Apartments were derived ultimately from the unspecified New York City apartment building.