Countries have made a range of international commitments to compile and use natural capital accounts. While processes and methods for compiling natural capital accounts are now well defined, mainstreaming natural capital accounting (NCA) across public sector decision-making remains a practical challenge. This raises the question: which domains of public sector decision-making are important for a phased introduction of NCA? Here, we address a subset of this evidence gap through systematic analysis of the policy-relevance of natural capital accounts in the United Kingdom (UK). We identify 85 UK public sector bodies whose activities can affect the extent or condition of natural capital assets, and 60 bodies whose policy objectives are qualitatively contingent on natural capital stocks or services. For each of these 60 public sector bodies natural capital management (1) is a core policy priority, (2) impacts on policy objectives by regulating natural hazards, or (3) provides ecosystem goods and services that support policy objectives concerning health and well-being. Our findings highlight the considerable cross-cutting relevance of natural capital for public sector decision-making, and the need to account for natural capital in policy domains beyond those focused narrowly on environmental policy and management, e.g. through coordination structures that feature cross-departmental representation.