As of 2016[update] the line is almost exclusively freight-only, with only a small segment within Chicago, between 21st Street in Chinatown and Ashland Avenue in Bridgeport, hosting Amtrak and Metra passenger trains.

From there to the interchange with the Indiana Harbor Belt Railroad in Broadview, Illinois, it is double-tracked and CTC-controlled.

The Illinois Central, after dropping the "Gulf" portion of its name in the late 1980s, reacquired the route in 1996.

[3] The IC operated the Illinois Central West Line on this subdivision in 1892 before discontinuing it in 1931.

[4] Passenger service returned on February 14, 1974, with the introduction of the Black Hawk between Chicago and Dubuque, Iowa.