The UK’s Arctic strategy is shaped by evolving geopolitical, military, and environmental challenges. Although not a part of the Arctic, the British Army plays a crucial role for the greater securitisation of the region. This paper examines the UK's defence contributions in the High North, focusing on military cooperation with Arctic states, strategic deterrence measures, and environmental considerations. Key initiatives such as Project Heimdall, the F-35 Lightning II program, and the Littoral Response Group (North) illustrate the UK’s commitment to NATO’s Arctic security framework. Additionally, UK partnerships with Arctic nations highlight collaborative approaches to Arctic governance. With increasing Russian and Chinese activity in the region, the UK’s role is crucial in maintaining stability through joint exercises and surveillance initiatives. The paper also explores future policy directions, including UK-Scandinavian security alignment and transatlantic defence shifts. Balancing military preparedness with environmental stewardship remains a core challenge for UK policymakers. As Arctic geopolitics continue to evolve, the UK's strategic role will be integral to shaping a secure and sustainable Arctic future.