Clydeside was formed as Clydeside Scottish in June 1985 from the northern operations of Western SMT to prepare the state-owned parent company, the Scottish Bus Group, for deregulation. At the time, Clydeside's operating area was much larger, covering Inverclyde, the Isle of Bute and much of the south side of Glasgow. Clydeside was re-merged with Western Scottish in 1989 in an attempt to make it more financially viable. However, on the privatisation of Western Scottish the Clydeside operations were sold in a management buyout as Clydeside 2000 plc with Luton & District taking a 23% stake. Clydeside began rationalising some of its operations, and depots at Largs, Paisley and Thornliebank were closed, the latter as a result of a reduction in operations within Glasgow. In November 1994, Clydeside 2000 was sold to British Bus, who had just completed the take over of shareholder Luton & District. The new parent company began investing heavily in the ageing fleet. A more vibrant red, white and yellow livery was introduced, and new "Flagship" routes were created to raise quality levels. Clydeside Buses was included in the 1 August 1996 sale of British Bus to the Cowie Group, which in November 1997 was rebranded as Arriva. The main competitor in Greenock, Ashton Coaches, was purchased along with 62 buses in July 1997. The Greenock operations were re-branded GMS Greenock Motor Services, using Ashton's white, green and gold livery, in order to more effectively combat the plethora of small operators in the town. Long established independent operator McGill's Bus Services of Barrhead was also purchased in the same month, and initially continued to operate under its own identity. A stake was also taken in Dart Buses of Paisley, another competitor, though this operator would soon go out of business. The company flirted with operations outside its operating area, successfully securing tenders to operate services in Cumbernauld and south east Glasgow, though these were short-lived. Further rationalisation took place in 2002, with the Inverclyde operations being sold to local management. Confusingly, the new operation was branded as McGill's Bus Services - the company name and operating licence having been purchased with McGill's of Barrhead - based in Port Glasgow, and employing a livery of blue, white and gold in the same styles as both Arriva and the GMS division, depending on what type of vehicle it was applied to. At the same time, the Barrhead depot, originally belonging to the initial McGill's Bus Service, was closed and operations concentrated on the two remaining depots. In 2007, BAA awarded the new Glasgow Flyer 500 service to Arriva, which bought several specially liveried Wright Eclipse bodied Volvo B7RLEs for the service. As a result, the 905 Airlink service, jointly operated with Fairline Coaches under contract to Scottish Citylink, ended; however Fairline have since started an independent service numbered 905. In August 2010 the company, along with First Glasgow, were banned by the area Traffic Commissioner from registering any new services into Glasgow city centre for six months after being found guilty of breaching regulations by picking up and dropping off passengers at locations other than their designated bus stops. One other operator was also banned. In December 2011, Arriva announced it had agreed to sell the business to McGill's Bus Services. The transaction was referred to the Competition Commission, before being approved in 2012.
Fleet
Below is a list of each depot fleet before the sale to McGill's. Most buses were transferred over to McGill's as part of the deal when the assets of Arriva Scotland West were sold to McGill's.
