BACKGROUND: Many people who engage in non-suicidal self-injury (NSSI) do not access support from health services, and evidence regarding the effectiveness of interventions is mixed. Despite this, NSSI prevalence rates decrease from adolescence into adulthood. Little is known about what helps alleviate difficulties with NSSI beyond psychological or medical intervention. This study sought to understand factors influencing naturalistic improvements in NSSI. METHODS: Semi-structured interviews were conducted over video call with 16 participants who believed their difficulties with NSSI had improved due to factors not attributed to psychological or medical intervention. Interviews were audio recorded and transcribed verbatim for analysis. RESULTS: A reflexive thematic analysis revealed four main themes. Increased insight into NSSI experiences promoted self-compassion and self-acceptance and enabled participants to reflect on the conflicting role of NSSI. Safe and supportive relationships helped alleviate loneliness, and developing alternative coping strategies enhanced feelings of control over self-injury. Creating a life guided by personal values promoted independence, choice, and self-esteem. CONCLUSIONS: The findings of the study highlight several internal and external naturalistic processes deemed meaningful in improving difficulties with NSSI. Clinical implications include the importance of developing and embedding these approaches within services and interventions to improve outcomes for individuals who self-injure while promoting a person-centred approach.