The need for a planetary approach to healthcare is widely recognised at national and international levels. Social prescribing is becoming an increasingly popular strategy for meeting contemporary social, physical and mental health needs as well as tackling health inequalities. As this is a relatively new and emerging healthcare intervention, a comprehensive and accurate understanding of its impact is essential to support continued improvements in care, develop strategies for scale-up and delivery and justify further funding and investment. Nature-based Social Prescribing (NBSP) has unique potential to affect animal and environmental outcomes as well as human health. The One Health perspective can be used to operationalise and evaluate NBSP. This article presents the Nature-based Social Prescribing Impact Pathways (NaBSPIP) framework, which can be used to guide NBSP design and evaluation to leverage maximum benefit for humans, animals and the environment that we share.