Operated by Stagecoach West under the brand name Oxford Tube, there are up to five coaches an hour via Lewknor, High Wycombe Coachway, Hillingdon, Shepherd's Bush and Baker Street terminating on Buckingham Palace Road, Victoria.

The former X90 route, which was operated by the Oxford Bus Company, ran up to two coaches an hour via Baker Street, also terminating on Buckingham Palace Road.

The Oxford Tube, launched by Thames Transit in 1987,[1][2] operates a fleet of Plaxton Panorama bodied Volvo B11RLE double-decker coaches.

[2] The Oxford Bus Company operated the X90 service every 15 minutes at peak times, using eight Plaxton Elite bodied Volvo B11Rs.

[7] From October 2018, the service was reduced to every 30 minutes,[8] and was withdrawn from 4 January 2020, due to a 35% fall in passenger numbers since 2015 causing the route to be unprofitable.

[9][10] In 1919 William Beesley of Oxford formed a company called South Midland Motor Services and by 1924 offered excursions to London by charabanc.

Varsity Express used the A40 via High Wycombe and Uxbridge, South Midland ran via Henley-on-Thames, Maidenhead and Slough.

Operations resumed in 1946, but by 1950 both Red & White and United Counties had been nationalised and were controlled by the British Transport Commission (BTC).

During the 1950s and 1960s, South Midland ran coaches between Oxford and London about every hour, alternating between the High Wycombe and Henley routes.

It was eventually curtailed at Heathrow Airport, but even then Thames Transit could not make it pay and in 1996 replaced coaches with minibuses and renumbered it X39.

[14] On 30 August 2010, a drunken 21-year-old grabbed hold of the steering wheel of an Oxford Tube coach and caused it to overturn on an embankment on the M40.