Between Ochanomizu and Mitaka, the Chūō line is used by two different local train services:

Chūō Rapid Line (Chūō Kaisoku-sen)
Main route is Tōkyō - Ochanomizu - Mitaka - Tachikawa - Takao (or parts thereof). Some services continues from Tachikawa to Ōme on Ōme line, other continues from Takao to Ōtsuki. It uses two of the four tracks ("Rapid tracks") between Ochanomizu and Mitaka. The trains do not stop at every station at this section - many stations do not have platforms for the Rapid tracks. Beyond Mitaka, the Chūō Rapid Line trains normally stops at all stations, but there are some "non-stopping" services.
Some early morning/late night trains originate in Tōkyō, use the local tracks (stopping at all stations) and continue beyond Mitaka.

Chūō-Sōbu Line (Chūō Sōbu Kankō-sen)
Through local train service from Chiba or Tsudanuma (Sōbu line) via Kinshichō - Ochanomiya to Mitaka. It uses the "Local tracks" between Ochanomiya and Mitaka and stops at all stations.

On the Nakano - Mitaka section, the Chūō line is also used by:
Tōkyō Metro Tōzai line
Tōzai Line trains from Nishi-Funabashi run Nakano - Mitaka on the "local tracks". Some trains originate in Tōyō-Katsutadai (Tōyō Rapid Railway) or in Tsudanuma (JR Sōbu line).


Between Tōkyo and Kanda, the Chūō line trains have their own double track alongside the Tōhoku line.
Between Yoyogi and Shinjuku, the Chūō line runs in parallel with Yamanote line.

At Kunitachi, there is a 5.0 km line to Shin-Kodaira at Musashino line. It is known as Musashino Kunitachi branch line. It is a freight line but it is used by the Rapid Musashino between Hachiōji and Ōmiya (1 eastbound and 2 westbound trains).