Abstract Long-term storage of banked sperm, especially when it is not needed, for reproductive purposes, is costly and poses practical problems for sperm banks. For sperm banks to function efficiently, men must understand the implications of unnecessary storage, and make timely decisions about disposal of their own samples. Men who bank sperm prior to cancer treatment are routinely offered follow-up consultations to test their fertility, update consent and, where necessary, expedite referral for Assisted Conception. Yet sperm banks report that men do not respond to letters, suggesting samples are stored needlessly. We conducted semi-structured interviews with six men with a history of not responding to letters, to document reasons for non-response. Interviews were transcribed and analysed using Interpretive Phenomenological Analysis. Men's reasons for not responding are a complex interplay between past, present and future perspectives. In terms of their past, information is important on diagnosis, because men must understand that fertility can change after treatment. Present and future concerns focus on fears of being told fertility has not recovered and being pressured to dispose of banked sperm. The challenge is to devise invitation letters that address men's concerns while offering them tangible benefits and peace of mind.