中央、總武緩行線
The Tōzai Line features through services on both ends. Trains run through onto the East Japan Railway Company (JR East)'s Chūō-Sōbu Line for at the western end, and onto either the Chūō-Sōbu Line for or the Tōyō Rapid Railway Line for at the eastern end, making the line an alternative route to the Chūō-Sōbu between and .