It served Folkestone Harbour with connecting boat train services across the English Channel to Calais and Boulogne.

The opening of the Channel Tunnel in 1994 made Folkestone Harbour uncompetitive, and the station began to decline, with regular passenger services ending in 2001.

After this, the line saw occasional steam rail tours and Venice-Simplon Orient Express (VSOE) trains, with the final service running in 2009 and it was formally closed in 2014.

[3][5] The harbour was extended over reclaimed land via a stone groyne gradually southwards to catch drifting shingle, which built up and allowed the SER to build a longer pier that ferries could use irrespective of the height of the tide.

[7] The SER planned to extend the branch line from Sandling to Sandgate to reach the harbour directly, but were blocked by the Earl of Radnor who owned the land.

As a consequence, all goods services along the Chatham Main Line were diverted to Folkestone Harbour to serve Boulogne or Calais.

[5] In December 1914, a daily service opened for war refugees from Folkestone Harbour to Holborn Viaduct via Orpington and Herne Hill.

Network Rail decided that it could not justify maintaining the route, so it began the process to close the station permanently, turning the viaduct into a pedestrian walkway.

[26] A small number of trains visited the branch thereafter; the final one was a steam-hauled rail tour by 70013 Oliver Cromwell from Victoria on 14 March 2009.

[21][29] On 21 December 2008, the Remembrance Line Association ran a railtour to the branch using the Southern Railway preserved diesel electric Class 201 No.

[30] On 20 March 2009, Network Rail announced they had begun the formal process to close the line and station on cost grounds, having redeveloped Folkestone West with new waiting facilities for the VSOE passengers.

By August 2010, the closure process had not proceeded past the statutory "mothballing" stage, making the railway still officially operational so that all objections could be properly addressed.

[33] In 2015, the Folkestone Harbour Company commenced a £3.5 million project to refurbish the viaduct and the station, retaining the remaining tracks, and repairing the canopies and the customs house.

[35] Though the station, viaduct and harbour have been extensively redeveloped, the northern part of the link to the main line has been mothballed, with no definitive plans.