A Primer on Blue Accounting and Finance

This paper examines the relationship between blue accounting and blue finance and its implications for sustainable ocean‐based development. Using a conceptual review of the United Nations Sustainable Blue Economy Finance Principles, major financial instruments, and selected cases, the paper shows that blue finance creates demand for standardized and comparable information, while credible blue accounting supports activity eligibility, environmental risk assessment, performance monitoring, and the prevention of bluewashing. It conceptualizes blue accounting as a connected architecture spanning corporate or entity‐level reporting, project‐ and financial‐instrument‐level accounting, and national or subnational ocean accounts. These levels serve distinct but complementary purposes across financial decision‐making, corporate management, public policy, and environmental governance. The analysis finds that existing accounting methods, including SEEA‐consistent ocean accounts, provide an important but incomplete foundation. Persistent difficulties in valuation, reporting boundaries, recognition, measurement, materiality, attribution, data availability, and institutional capacity limit their effectiveness. Addressing these limitations requires combining established approaches with marine‐specific definitions, ecological indicators, valuation methods, and stronger connectivity across accounting levels. Blue finance should therefore be understood as part of a broader institutional transition aligning accounting, governance, and capital allocation with ecosystem resilience.