Sidney Claridge was born on 3 February 1897 at Lambeth, London, the son of Richard and Rose Claridge of Oxford. His Father, Richard, was an Army Sergeant who died in uniform in January 1917 aged 58.

Before joining the Royal Navy on 16 May 1913 at HMS GANGES, as a Boy 2nd Class, Sidney was a shop assistant. After training at HMS IMPREGNABLE he was advanced to Boy Telegraphist on 11 May 1914 and was then drafted to HMS VERNON on 9 September 1914. He then served in the cruiser HMS TOPAZE and the battleships HMS PRINCE OF WALES and VICTORIOUS, where he was advanced to Ordinary Telegraphist, between October 1914 and February 1915.

On 13 February 1915 he joined HMS DOLPHIN for submarine training before being drafted to HMS MAIDSTONE, for HMS E16, on 23 March 1915.  He was further advanced to Telegraphist on 14 June 1915.

Sidney Claridge died in the sinking of HMS E16 in the North Sea on 22 August 1916 and is commemorated on the Chatham Naval Memorial and the war memorial at Oakley, Buckinghamshire.