He was on HMS Resolution under Captain Lord Robert Manners in Rodney's action of the Battle of the Saintes against the French on 12 April 1782[1][5] His commission for service at the rank of 4th Lieutenant was issued in 1784.

Following representations made by Charles Grey, to John Pitt, 2nd Earl of Chatham detailing the career of his son George, also a lieutenant in the navy, and requesting consideration for promotion, he was on 7 August 1793 confirmed as Captain of HMS Vesuvius (1776).

During the Battle of Cape St Vincent of 14 February 1797, despite the heavy fighting, there was only one fatality on HMS Victory, when a Marine was shot alongside John Jervis on the poop deck.

[15] The service record of George Grey as Adjutant General of the Fleet whilst on Argo and Guerrier from June to November 1799 by Evan Nepean 26 Dec 1801[16]

Lord St Vincent was desirous of calling to his assistance in the Channel, as many as he could of the Officers formed in the Mediterranean Fleet... That the Admiralty could not, at a moment's notice, comply with these wishes as fully as his Lordship imparted them, may also be as easily supposed.

[18] The Grey family lived at Weymouth for the three years of his service to King George III and a doll's house that was presented to his daughters by the Royal princesses is on display at Kew Palace.

During his time there, on 23 December 1805 his official yacht, the Chatham, was used to transfer Horatio Nelson's coffin with his flag flown at half mast, from HMS Victory to Greenwich Hospital.

Besides overseeing the changing face of the Navy and the Dockyard being instigated by the Lord of the Admiralty, Earl St Vincent, Sir George had an important administrative role to play.

Some of his correspondence with the Navy Board from 1807 to 1827 is still kept by National Archives relating to the workers, maintenance and general operation of the dockyard, including major accidents.

[22] In 1814 during a royal visit instigated by the Prince Regent (later King George IV), Emperor Alexander I of Russia, Catherine, Grand Duchess of Oldenburg, the Earl of Yarmouth, and Russian Ambassador Count Lieven stayed at the Commissioner's residence in Portsmouth Dockyard.

[25] In addition to his work as Commissioner of the Dockyard he was also Marshal of the Vice-Admiralty Court at Barbados; an Alderman of Portsmouth and Vice President of the Naval and Military Bible Society.