 Lion became the flagship of Vice-Admiral W. C. Pakenham in December 1916 when he assumed command of the Battlecruiser Fleet upon Beatty's promotion to command of the Grand Fleet. Lion had an uneventful time for the rest of the war, conducting patrols of the North Sea as the High Seas Fleet was forbidden to risk any more losses. She provided support for British light forces involved in the Second Battle of Heligoland Bight on 17 November 1917, but never came within range of any German forces. The 1st BCS, including Lion, sailed on 12 December in a futile attempt to intercept the German destroyers that had sunk the convoy en route to Norway earlier that day, but returned to base the following day. Lion, along with the rest of the Grand Fleet, sortied on the afternoon of 23 March 1918 after radio transmissions had revealed that the High Seas Fleet was at sea after a failed attempt to intercept the regular British convoy to Norway. However, the Germans were too far ahead of the British and escaped without firing a shot. When the High Seas Fleet sailed for Scapa Flow on 21 November 1918 to be interned, she was among the escorting ships. Along with the rest of the 1st BCS she guarded the interned ships until she was assigned to the Atlantic Fleet in April 1919 and then placed in reserve in March 1920. Paid off on 30 March 1922, despite a press campaign to have her saved for the nation as a memorial, Lion was sold for scrap on 31 January 1924 for £ 77,000 to meet the tonnage limitations of the Washington Naval Treaty.
