The U.S. Post Office and Courthouse is a post office and federal courthouse located at 200 North Eighth Street in Quincy, Illinois. The building was designed in 1885 and completed in 1887. Architect Mifflin E. Bell, Supervising Architect at the time, designed the French Renaissance Revival style building. Bell's design was inspired by Richard Morris Hunt's design for the William K. Vanderbilt House in New York City; at the time, the French Renaissance Revival style had not spread to Illinois, which made Bell's work distinctive in the region. The building's design features a limestone exterior, arched entrances and first-floor windows, and an ornate roof with pointed gables and dormers.