Promoting positive transition to retirement and cultural adaption for ex-service personnel has been identified as a priority for both social-science research and for public health policy in the UK. The Royal British Legion aims to provide support to service and retired service personnel, but to date the transition to retirement experiences of older (60-plus) ex-service personnel remain under-researched. In this article, we employ a symbolic interactionist theoretical framework to examine older servicemen’s experiences and identity challenges post-retirement from the British armed forces. Data were collected primarily through semi-structured, focus-group interviews with 20 former servicemen. Here, we focus specifically upon the challenges encountered by these ex-servicemen in the retirement transition from military to civilian life, a time of identity flux of sociological interest. To navigate this period of identity change and challenge, many participants constructed a ‘modified military self’ through involvement with the Royal British Legion as a key social support network. For many retired personnel the Royal British Legion offered a form of identification and group identity that resonated strongly with earlier experiences of comradeship in the military.