Sudbury is an unstaffed station with one platform as the line is single-track, and with a self-service ticket machine.

[6] An 1886 plan of the station area showed two platforms and a back road used for goods trains.

In addition to the existing signal box located just west of Sudbury station, Sudbury Goods Junction signal box was opened, located east of the station and controlled a level crossing and entrance to the goods yard and engine shed.

[8] On the last day of the GER (31 December 1922) the following locomotives were allocated to Sudbury:[9] After the grouping of 1923 operation of the station passed to the London and North Eastern Railway (LNER).

[6] The station was unstaffed from 14 August 1966, when Paytrain operation of the line began, and local goods services were withdrawn on 31 October 1966.

Sudbury became a terminus again following the Beeching cuts to railway services, which led to the closure of the through Stour Valley route on 6 March 1967.

[12] Despite the fact that all of the track bar a single line into the platform remained, Sudbury Goods Junction signal box was retained to control the level crossing.

In 1982, following the sectorisation of British Rail, the station became part of the London and South East sector, which was renamed Network SouthEast in July 1986.

The 18:05 service from Marks Tey was travelling at a speed at the time of the collision of approximately six miles per hour.

[14] The typical off-peak service is one train per hour to Marks Tey, with frequency increased slightly during the weekday peak:[15] July 1922 was during the last summer of Great Eastern Railway operation before the LNER took over I January 1923.

Down services were towards Bury St Edmunds and Cambridge (the line split at the next station Long Melford) and towards Marks Tey in the up direction.