The line to Ayr was electrified and Class 318electric multiple units introduced by British Rail in September 1986. The line was promoted as the AyrLine in Scotrail publicity. Along with the introduction of new trains, major work was undertaken refurbishing stations, major trackworks and rebuilding many bridges. At the same time resignalling was carried out, replacing the existing semaphore signals.[1] The full electrified service, including trains to Largs and Ardrossan Harbour, commenced on 19 January 1987.[1] These were supplemented by occasional use of Class 303 and Class 311 EMUs, then in use on the Inverclyde Line.
These EMUs replaced the Class 101 and Class 107 DMUs that had served the line for over 30 years. Class 126 DMUs were also used on the line, but they succumbed to old age in the early 1980s.
Services 2023
As of December 2023, There are 4 trains per hour running every 15 minutes between Glasgow Central and Kilwinning, 2 of these continue to Ayr while 1 an hour serves Ardrossan Harbour and Largs each. Extra trains run at peak hours with all trains calling at Paisley Gilmour Street, Johnstone and Kilwinning. There are occasionally extra services which run to/from Ardrossan Harbour to connect with CalMac sailings to/from Brodick on Arran, There is an hourly service which runs between Kilmarnock and Ayr which calls at Troon and at Prestwick* On a Sunday, there are 3 trains an hour, 2 to Ayr and 1 to Largs and 4 trains per day to/from Ardrossan Harbour to connect with ferries, There are no Sunday services to/from Kilmarnock.
Not all Kilmarnock trains call at Prestwick Town and they do not call at Prestwick Airport