[7] In December 1906, it was announced by the British Admiralty that the coastal destroyers would be reclassified as torpedo boats, and would be known by numbers rather than names.

[7] The newly completed TB 4 was accepted from Whites and commissioned with a nucleus crew[d] as a tender to the depot ship Hecla at Portsmouth naval base on 17 April 1907.

[23] On 17 November 1915, the hospital ship Anglia, carrying a load of sick and wounded soldiers back to Britain from France, struck a mine off Folkestone.

Other survivors were rescued by the torpedo gunboat Hazard, the steamships Langdon and Channel Queen, and the collier Lusitania, which also struck a mine and sank.

[24][25] On the night of March 17/18 1917 Germany launched a major raid by torpedo boats based in Flanders against Allied defences and shipping in the English Channel.

While two groups of torpedo boats were to operate against the Dover Barrage, four more were ordered to attack shipping on the Downs.

[26][27] while the attack on the Downs sank the steamer SS Greypoint and damaged the naval drifter Redwald before firing a few shells at Ramsgate, Broadstairs and St Peter's.

[31] By March 1919, TB 4 was in reserve at Devonport,[32] and by January 1920, was, together with most of the remaining torpedo boats, listed as being for sale.