National expansion
Starting in 1914, with the LGOC dominant in London, the company looked to the rest of Britain outside London for growth. Tilling started to seek new markets in the provinces. The company began operating in Folkestone in 1914, Brighton in 1916, and Ipswich in 1919.
BET had entered into a similar agreement with LGOC in London, and was also expanding outside London. Instead of destructive rivalry, the two companies agreed to work in close co-operation. By 1928, a BET subsidiary, British Automobile Traction Company (BAT), had interests in nineteen bus companies, with Tilling being a co-owner of eleven of them, and at the same time was partly owned by Tilling itself. To simplify the arrangement, BAT was reconstructed with a new title, Tilling & British Automobile Traction Ltd (TBAT), and Tilling exchanged its shares in the various operating companies for an increased shareholding in the new company.[2][8]
The railways of Britain had grown significantly and many companies had developed bus services. In 1923, most of these "pre-grouping" companies merged to form four mainline companies: Great Western Railway; Southern Railway; London, Midland and Scottish Railway; and London and North Eastern Railway. During the 1920s, the "Big Four" divested themselves of much of the operations of their bus networks by transferring their interests to Tilling and BET in exchange for shares.
The Tilling family's association with the company ended in 1929 with the death of Richard Tilling. In 1931, Thomas Tilling Ltd acquired the Bristol Tramways and Carriage Company, along with the Eastern Counties Omnibus Company, whose bus construction activities were renamed the Eastern Coach Works Ltd (ECW) in 1936.[8]
In 1933, the new London Passenger Transport Board compulsorily acquired the 328 buses that made up Tilling's South London services.[2] In 1935, Tilling took over Royal Blue, which was the premier express coach company in the South and West of England, with a network of routes stretching from Penzance to Margate and Bournemouth to London, having developed tours and local services around Bournemouth and the New Forest in the horse-drawn era and express coach services after the First World War.[10]
Tilling and TBAT continued to trade successfully, but internal disagreements resulted in TBAT being wound up in 1942.[8] The companies in TBAT were split between Tilling and BET, and the two groups continued to operate independently until nationalisation began in the late 1940s. Tilling Motor Services Ltd was formed from the break-up.[8]