All four of the "King George V"-class ships were assigned to the 2nd Battle Squadron on commission, "King George V" becoming the Squadron's flagship by 18 February 1913, but "Centurion" began her career early, accidentally ramming and sinking an Italian steamer with all hands. From 17 to 20 July 1914 the sister ships participated in the July Crisis test mobilisation and were shortly thereafter ordered to join the Home Fleet, soon the Grand Fleet, at Scapa Flow. On 27 October 1914, "Audacious" struck a mine while conducting a training mission off the coast of Ireland and sank with only one death, an officer from . "King George V" also went out of service for a brief time beginning in November 1914 because of a condenser malfunction. The surviving sisters participated in a sortie that set out to engage Franz von Hipper's raiding force after its attack on three coastal British towns in December 1914, but did not see combat. At the Battle of Jutland nearly two years later, the sisters did see combat but none of them fired more than 19 shells, all without effect due to poor visibility. The sisters participated in the Royal Navy's subsequent war time actions and were present at the surrender of the German fleet at Rosyth on 21 November 1918. Into early 1919, the sisters remained with the 2nd Squadron, until "King George V" was moved to the 3rd Squadron and then became the flagship of the Reserve Fleet until 1920 when the 3rd Squadron was disbanded. She was refitted and reassigned to the 4th Squadron the same year, then in 1923 became a gunnery training vessel before finally being sold for scrap in December 1926. "Ajax" met the same fate, but was sold for scrap on 9 November 1926. The last of the "King George V"-class ships, "Centurion" was converted into a target ship, but was remilitarised in 1941 with light weapons and dummy main guns. On 9 June 1944, she was sunk as a block ship to defend a mulberry harbor established on Omaha Beach.