The line initially had only five new stations: Lee, Eltham (now Mottingham), Sidcup, Bexley and Crayford.

The Loop Line originally passed through mainly open country and farm land but it stimulated development around the new stations.

This allowed direct running between the two routes, avoiding the need for a reversing manoeuvre at Dartford.

In the late 1960s the Dartford Loop Line along with the two other North Kent routes were re-signalled which saw the replacement of semaphores with colour light signals.

[6] Train services on the Dartford Loop Line are operated by Southeastern using Class 376, 465, 466 and 707 EMUs.

As of December 2022, the off-peak, Saturday and Sunday service is:[7][8] During the peak hours, the line is served by an additional 2 trains per hour circular service to and from London Cannon Street which runs both clockwise and anticlockwise using the Dartford Loop Line as far as Crayford, before using the North Kent Line to travel back to London Cannon Street via Woolwich Arsenal and Greenwich.

In addition, there is a single peak hour return service between Dartford and London Blackfriars and a number of services are extended beyond Gravesend to and from Strood and Gillingham During the peak hours.