In the 1930 renumbering of state highways in New York, the portion of what is now NY 263 south of Getzville was designated as part of NY 270. NY 263 was assigned by the following year; however, it initially followed a significantly different alignment than it does today. At the time, the route extended from NY 270 south of Getzville to NY 93 northwest of Akron by way of Millersport. West of Millersport, NY 263 utilized a short portion of its current alignment before taking a more northerly path along Hopkins Road and Tonawanda Creek Road. At Millersport, the route overlapped with NY 78 south to Wolcott Road, from where it continued northeast through Clarence on Wolcott and Goodrich Roads.