The garage at Stony Stratford operated by a fellow Tillings company, Eastern National was transferred to United Counties.

The company built new garages in several towns, a new headquarters, with major engineering workshops, in Bedford Road, Northampton, and a central covered bus station at Derngate, Northampton, thus putting it into a good shape to withstand the rigours of wartime operation.

In 1952 Eastern National's operations in Bedfordshire, Buckinghamshire, North Hertfordshire and Huntingdonshire, with some 250 vehicles, were transferred to United Counties.

[8][9] There followed a period when the company was under severe pressure in coping with the maintenance of the Luton combined fleet and for a time had to forgo its duty to deal with the recovery of fellow National Bus Company subsidiaries’ coaches broken down on its allocated and very busy section of the M1 motorway.

However, the trading names and the legal titles remained as before, until October 2014, when the "United Counties" registered address was changed to match the Warwickshire operations and thus "Midland Red (South) Ltd and United Counties Omnibus Company are registered as being based in Northampton.

Luton & District was bought in 1994 by British Bus,[18] which, in turn, was purchased by the Cowie Group on 1 August 1996 and rebranded as Arriva the Shires in 1998.

[19][20][21] Milton Keynes Citybus was acquired by Cambus (a privatised part of Eastern Counties), which was, itself, sold to Stagecoach in 1996.

However, after the inquiry by the Office of Fair Trading, Stagecoach sold both the Milton Keynes and Huntingdon depot operations to Julian Peddle on 2 May 1997, who formed Premier Buses[22] and MK Metro.