Devon General was the principal bus operator in south Devon from 1919. The name was first used by the Devon General Omnibus and Touring Company which was created in 1919. In 1922 it was purchased by the National Electric Construction Company which merged with British Electric Traction in 1931. Nationalisation in 1969 resulted in 1971 with the company being merged into Western National. In 1983 a new Devon General Limited was created which became the first operating subsidiary of the National Bus Company to be privatised in 1986 when it became the first company of Transit Holdings. It was sold to the Stagecoach Group in 1996 and renamed Stagecoach Devon in 2003.

Coaches were operated under various names, principally Fleet Cars from 1925 until 1933, and Grey Cars from 1932 until 1971.

Its main principal depots were in Exeter and Torquay, but the area of operation covered most of south, east and mid Devon.

The Devon General Omnibus and Touring Company started operations in south Devon in 1919 with two bus routes from Exeter to Torquay. In 1922 Torquay Tramways bought the company for £36,000, although it was operated as a subsidiary of the National Electric Construction Company (NECC) and the motor buses already owned by the tramway company were transferred to Devon General. Some charabanc tours had been operated by the Torquay Tramways and this continued under Devon General. A local independent company that traded as Fleet Cars was purchased in 1925 but continued to operate as a separate business for a few seasons, during which time a number of other small operators were also acquired and merged with Fleet Cars.

In 1931 the NECC became a part of British Electric Traction (BET). The Torquay tram network was closed in January 1934. The Tramways company was sold to Devon General, the fleet of which was enlarged by 24 buses to allow it to operate the former tram routes.

Devon General had turned down the chance to buy local independent coach operator Grey Cars in 1930 so it had instead been purchased by A Timpson & Sons of Catford in 1931. Timpsons sold the business to Devon General in 1932 and the following year both Grey Cars and Fleet Cars, which had been operated as separate businesses, were merged into Devon General. Most coaches continued to operate under Grey Cars' name, although some small operators that were subsequently bought out by Devon General continued in their old names for a while.

BET's bus operations, including Devon General, became part of the National Bus Company (NBC) when it was formed on 1 January 1969. Devon General had worked closely with the Corporation of Exeter's bus services since 1947. In April 1970 the corporation's buses and routes were transferred to the NBC and merged into Devon General. The city's unusual use of route letters (as opposed to numbers) continued.

In January 1971, the NBC transferred the bus operations of Devon General to neighbouring Western National but the Devon General name was retained as a brand, while the Grey Cars coaching operation was transferred to Exeter-based Greenslades. NBC split Western National into four new companies on 1 January 1983, one of which was Devon General Limited. This operated in south and east Devon as the old Devon General had done, but the Tiverton area became a part of a new North Devon operation.