Social capital, and more particularly the social networks that define its existence, is said to benefit health and well-being. In individuals recovering from alcohol and drug addiction, social capital accruing from social networks support treatment, recovery and maintenance. Therefore, the concept of social capital is important for public health practitioners working in recovery interventions. This qualitative study seeks to explore what practitioners perceive as the importance of social capital and how they apply the concept in interventions to support individuals recovering from drug and alcohol addiction. Eight public health practitioners involved in drug and substance abuse interventions in West Yorkshire, England, were interviewed. The results of the interview were then deductively coded using two priori themes of perceived impact of social capital on health outcomes and application of social capital theory in recovery interventions. The findings reveal that practitioners understand the impact of social capital as the effects of social networks on recovery and apply the concept in their interventions. However, the nature of interventions created based on similarities in condition (alcohol and substance addiction) and intended outcome (recovery) create bonding social capital with mixed outcomes. This paper argues that the wider benefits to service users are unintentionally inhibited by the overwhelming downsides of bonding social capital. For instance, closed support groups comprised of individuals with high similarities further exclude the already socioeconomically deprived service users from integrating and accessing resources outside their groups.