Komachi trains couple with Hayate trains on the Tōhoku Shinkansen for the portion of the journey between Tokyo and Morioka. Between Morioka and Akita, the Komachi runs as a six-car independent train. It uses E3 series rolling stock.
March 22, 1997: The segment from Morioka to Akita began operating on with E3 series trains, 5 cars long.
1998: Trains extended to 6 cars
September 16, 2001: line celebrates 10 millionth passenger.
March 11, 2006: line celebrates 20 millionth passenger.