[30] On 21 October 2011, Defender left Scotstoun shipyard in Glasgow on her maiden voyage exactly two years to the day after she was launched, to conduct her first stage of sea trials.

[34] Defender was part of Operation Shader, employed as an air defence guard ship for the US Carrier Task Force 50, in 2014.

[38] In June 2016, Defender, in conjunction with Australian and French ships, seized a total haul of 1020 kg of hashish from a fishing dhow south of Oman.

[39] Defender returned to active service in early August 2018, after a major 18-month long refit in Portsmouth, in the course of which she was fitted with the Shaman communications electronic support measures (CESM) to be used for the purposes of signals intelligence.

[41][42] In December 2019, Royal Marines from Defender confiscated 131 kg of crystal meth after searching a dhow in the Arabian Sea.

[46][47] On 27 June, it was reported that secret documents relating to the passage of HMS Defender through Ukraine's territorial waters had been discovered at a bus stop in Kent.