The St Helens trolleybus system once served St Helens, Merseyside, north west England. Opened on 11 July 1927, it gradually replaced the St Helens tramway network.
By the standards of the various now-defunct trolleybus systems in the United Kingdom, the St Helens system was a medium-sized one, with a total of six routes, and a maximum fleet of 66 trolleybuses. It was closed relatively early, on 30 June 1958. The 16 youngest trolleybuses in the fleet at that time, ones built in 1950–51, were all sold to other systems for further use. Eight Sunbeam vehicles went to South Shields system and eight British United Traction vehicles to Bradford.
Only one of the former St Helens system trolleybuses is now preserved, owned by the Trolleybus Museum at Sandtoft.
Although 389 finally saw service in Bradford, it has been restored into St. Helens colours. its bradford fleet number can still be seen in the cab.
When the vehicle eventually returns to the Museum after its loan to the North West Museum of Road Transport, it is intended to restore its running gear so that it can run in service once again.