The Indiana State Highway Commission proposed SR 227 initially as part of the state road system by August 1930.[3] This section of highway ran from Richmond to SR 28 (now SR 32) roughly along the modern routing. By September 30, 1930, the highway official became part of the state road system.[4] SR 227 was extended south to the Ohio state line in late 1950 or early 1951, replacing SR 21.[5][6]
^ abIndiana Department of Transportation (July 2015). Reference Post Book(PDF). Indianapolis: Indiana Department of Transportation. Retrieved July 6, 2016.
^Indiana State Highway Commission (August 1, 1930). State Highway System of Indiana (Map). Indiana State Highway Commission. Retrieved July 6, 2016 – via Indiana State Library and Historical Bureau.
^Indiana State Highway Commission (September 30, 1930). State Highway System of Indiana(PDF) (Map). Indianapolis: Indiana State Highway Commission. Retrieved July 6, 2016 – via Indiana University Bloomington Libraries.
^Indiana State Highway Commission (1950). State Highway System of Indiana (Map). 1:656,700. Indiana State Highway Commission. OCLC53353668. Retrieved July 6, 2016 – via Indiana State Library and Historical Bureau.
^Indiana State Highway Commission (1951). State Highway System of Indiana (Map). 1:660,000. Indiana State Highway Commission. OCLC64558142. Retrieved July 6, 2016 – via Indiana State Library and Historical Bureau.