The notions that military violence engenders security and that military service is a selfless and necessary act are orthodoxies in political, military and scholarly debate. The UK Army Reserve’s recent expansion prompts reconsideration of this orthodoxy, particularly in relation to the suggestion that reservists serve selflessly. Drawing on fieldwork with British Army reservists and their spouses/partners, we examine how this orthodoxy allows reservists to engage in everyday embodied performances, and occasionally articulations, of the need to serve, in order to free themselves up from household responsibilities. This supposed necessity of military service necessitates heteropatriarchal divisions of labour, which facilitate participation in military service and the state’s ability to conduct war/war preparations. However, while reserve service is represented as sacrificial and necessary, it is far more self-serving and is better understood as ‘serious leisure’, an activity whose perceived importance engenders deep self-fulfilment. By showing that the performances of sacrifice and necessity reservists rely on are selfish, not selfless, we show how militarism is facilitated by such everyday desires. We conclude by reflecting on how exposing reserve service as serious leisure could contribute to problematizing the state’s ability to rely on everyday performances and articulations of militarism and heteropatriarchy to prepare for and wage war.