Initally, the first batch of units were introduced by British Rail to operate the newly electrified route from London St Pancras to Brighton in 1981, however only 3 years after introduction newer units began to replace them thanks to the incorporation of the Bedford route into the new Thameslink programme. They made the move onto outer suburban services on the West Coast Main Line, operating from London Euston to Milton Keynes and Northampton. This work was again short lived, as Class 321s began to replace them on the West Coast Main Line two years after their introduction. Following this cascade the units were moved East, on runs out of London Kings Cross and Liverpool Street. Here they joined the second batch of units, which were built for this work during 1985 and 1986.

After a tumultuous introduction in the 1980s the Class 317s settled well into their role on services between London and Cambridgeshire, thanks in part to a programme to extend the electric wires which eventually reached Kings Lynn by 1992. The original structure of operators in the region at the beginning of privatisation meant all Class 317s were operated by West Anglia Great Northern, however a shake up of the borders of each operator in 2004 meant the units were split between First Capital Connect and National Express East Anglia. Many other operators had also made use of the Class 317 by this point, as many were often available for sub leasing by WAGN and later FCC for use on LTS rail and Thameslink.

By the end of the 2010s the fleet of twelve FCC, now Great Northern, units had been withdrawn and moved across to Greater Anglia thanks to new units being made available. Greater Anglia began to follow in the 2020s, with the introduction of the new Class 720 fleet. Unrefurbished units began to be withdrawn as 720s began operations on the WAML, however the last units ran on Greater Anglia services as recently as 2022. This was because some members of the fleet were fitted with more up to date disabled access and universal toilets, this made them the obvious choice for a later withdrawal compared to the younger Class 321s, many of which had not received the same upgrades. Following withdrawal by Greater Anglia and a short period in storage, DTSO 77092 of unit 317345 was purchased by the East Anglian Railway Museum in 2022. Since its move to the site in Chappel and Wakes Colne it has been returned to Network SouthEast livery, and will feature within a large exhibit focussing on the electrification of the lines in the Anglia region.

(1) Greater Anglia 317506 at London Liverpool Street. (2) Greater Anglia Class 317s 504, 339, 881 and 508 in storage at Ely Papworth Sidings. (3) Greater Anglia Class 317 First Class interior. (4) Network SouthEast DTSO 77092 (Ex Class 317 317345) at the East Anglian Railway Museum. (5) Greater Anglia 317501 at Cambridge North.

Additional information on the Class 317

Clacton Express Preservation Group

https://www.clactonexpresspreservationgroup.com/