Project Aperta: enabling cross-border interconnectivity through open finance interoperability

Project Aperta, led by the Bank for International Settlements (BIS), has been designing, developing and testing a prototype for cross-border open finance interconnectivity via application programming interfaces (APIs) – a "network of networks" that connects existing domestic networks through a neutral interoperability layer. The prototype connects the open finance networks of the United Kingdom, the United Arab Emirates, Brazil, Hong Kong SAR and India.

The project was carried out by the BIS Innovation Hub Hong Kong Centre in collaboration with central banks, regulators, international organisations and academia. The prototype was tested with private-sector commercial banks and fintechs.

Project Aperta was designed as an experimental initiative, with SME banking and trade finance serving as concrete test cases for the prototype.

Relevance to central banks and next steps

Project Aperta demonstrates that secure cross-border data portability is feasible within the existing banking ecosystem. By showing what is technically achievable, the project enables policymakers to assess the benefits of interconnecting domestic open finance networks and to refine the architecture for potential real-world implementation. It also serves as a regulatory testbed, helping to identify potential legal, governance, and technical adjustments needed to support interoperability and secure data sharing.

Looking ahead, central banks and regulatory authorities could build on these findings to explore practical deployment pathways. One approach could involve small clusters of jurisdictions with advanced open finance ecosystems piloting use cases aligned with central bank mandates, particularly those aimed at improving payment system efficiency and supporting financial stability. Such tests could generate the operational, legal, regulatory, and governance insights needed to inform broader adoption and, over time, support the development of scalable cross-border digital financial infrastructure.

Report structure

This report provides background on the concept of open finance, its benefits, and the main outputs of the project. It explains how Aperta enables cross-border data portability through open finance, outlines the prototype's technology components and design considerations, and summarises the key findings as well as possible directions for future development.

All architectural documents, translation protocols, trust and identity system designs, reference code, and data models have been developed as shared goods for the central banking community and are available for other jurisdictions and network operators to use as a foundation for learning and further development.

Central banks, regulators, governments, and network operators interested in the blueprints, prototype assets, or further collaboration are invited to contact the Project Aperta team at hongkong.centre@bisih.org.