South Midland

The Oxford to London coach route is an express coach route between Oxford and London along the M40 motorway. The Oxford Tube, which is operated by Stagecoach, runs up to five coaches an hour via Lewknor, Hillingdon in West London, and Shepherd's Bush, and terminates on Buckingham Palace Road, Victoria. The X90, which is operated by the Oxford Bus Company, runs up to three coaches an hour via Baker Street and terminates on Buckingham Palace Road.

With a total of 150 journeys a day in each direction it is the highest frequency long distance coach route currently operating in the United Kingdom. By way of comparison, there are 15 coach journeys a day from Cambridge to London.

The Oxford Tube operates a fleet of 26 Van Hool Astromega TX27 double decker coaches that were introduced in July 2014. Rather than turnover its fleet on a regular basis, Oxford Tube renews its entire fleet in one go every five years.

Tickets are also sold via the Megabus network.

The Oxford Bus Company operates the X90 service every 15 minutes at peak times, using Plaxton Panther bodied Volvo B12B coaches. and are fitted with advanced telematics resulting in a fuel consumption of 10.37 mpg_‑imp (27.2 l/100 km), which works out at 468 mpg_‑imp (0.604 l/100 km) per seat.

In 1919 William Beesley of Oxford formed a company called South Midland and by 1924 offered excursions to London by charabanc. This became a daily service, and by 1928 it had become a regular coach service picking up and setting down passengers en route.

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