B. Weatherill Ltd, started by Weatherill's father, Bernard B. Weatherill, began as a 'Civil, Military and Sporting Tailors' and had a particularly prosperous phase during the First World War, when orders were received from the military for uniforms. At this time there were shops in Ascot, Aldershot and Camberley, although some of these closed at the end of the war. However, various premises were used for the business in central London, mainly in Conduit Street, which continued to be used until they were bombed out in 1939. In the meantime the business took over various other tailors businesses, and also had branches in New York as Bernard Weatherill Inc and in South Africa.
In 1982 the company merged to become Kilgour Weatherill, though maintained its reputation, particularly in making riding outfits. It is from this branch of its work that it received its royal warrants and the Royal family continue to use the firm in this respect.