On 30 August 1912 the Admiralty directed all destroyer classes were to be designated by alpha characters starting with the letter 'A'.

After 30 September 1913, she was known as an E-class destroyer and had the letter ‘E’ painted on the hull below the bridge area and on either the fore or aft funnel.

[5][6] Upon her return to Home Waters 1914 she was in the 9th Destroyer Flotilla based at Chatham tendered to HMS St George.

[7] Exe was still based at Scapa in January 1915,[8] but in February, it was decided to base more destroyers in the English Channel to protect troop transports, and Exe was ordered to join the Sixth Flotilla, part of the Dover Patrol, leaving Scapa on 27 February and arriving at Dover on 2 March.

[11] On 15 December 1916 Exe and sister ship Cherwell were mid-English Channel, returning from escorting a convoy to Le Havre when they interrupted the German submarine UC-17, which had stopped the British steamer Red Rose.

[13] On the night of 13/14 May Exe was escorting the merchant ship SS Irwell between Portsmouth and Le Havre when her commanding officer spotted a possible submarine.