The line was opened in three stages by the London, Brighton and South Coast Railway (LB&SCR) between 1848 and 1863, creating what was then known as Mid-Sussex route to Portsmouth.

A single track branch line was opened on 14 February 1848, with passing places at the intermediate stations at Crawley and Faygate.

The stations now at Ifield and Littlehaven were not opened with the line, both being opened on 1 June 1907: Ifield as Lyons Crossing Halt and Littlehaven as Rusper Road Halt; both serving the outskirts of their nearby towns.

For most of the rest of the twentieth century, an hourly express service was provided which joined/divided at Barnham, with 4 or 8 coaches continuing to Bognor and 4 to Portsmouth Harbour.

[4] An all-stations stopping service also ran hourly via Crawley to Bognor Regis, usually via Littlehampton.

The line was completely closed to traffic during these major engineering works and a replacement bus service served stations between Arundel and Pulborough.

As the two-week Arundel Festival was drawing to a close over the weekend, Southern maintained a service into the station from the West Coastway Line from Bognor Regis via Barnham and Ford, and a reversal at Littlehampton.

Down-line services: Both divide at Horsham, the train closest to the hour has a front portion which is fast to Barnham then stopping to Portsmouth Harbour.

The 30-minutes-past train's front portion again runs fast to Barnham then is semi-fast to Portsmouth Harbour.