ÍST TS-313 defines web application programming interfaces implemented by Icelandic commercial and savings banks to expose shared functionality and information for foreign payments, under the Icelandic Online Banking Web Services (IOBWS) framework of specifications. Other ÍST Technical Specifications exist which address related but discrete units of the overall IOBWS framework, either as new additions or upgrades to the previous specifications. Some crosscutting guidelines and shared concerns are addressed in the workshop agreement ÍST WA-316. As the consumption and implementation of each part of IOBWS are optional, the documents aim to be independent of each other. However, due to the origin of the underlying OpenAPI specification in the Berlin Group NextGenPSD2 Framework, ÍST TS-310 on Domestic Payments and Deposits and ÍST TS-313 on Foreign Payments overlap quite significantly. Both are based on the “IOBWS3.1.yaml” definition document and share schema type and API service definitions. They will still be treated as separate entities, but stakeholders are advised to reference the other document if more context is required. The focus in ÍST TS-313 is the following: the domestic adaptations to the relevant parts of the NextGenPSD2 framework; as well as the information needed to tie that to earlier IOBWS versions or other such implementations, including the Core Banking systems involved. The intended audience for the specification document ÍST TS-313 is those who are implementing banking services and systems that will consume them as API clients. The reader is expected to have a basic understanding of the Icelandic financial products involved. Further documentation on business aspects of those products will be available from each bank, as they may involve service agreements and the end customers’ contractual preferences and benefits. Consequently, the ÍST TS-313 specification avoids the unnecessary repetition of information found in the technical contract IOBWS3.1.yaml. Instead, the rest of the document focuses on the information needed to understand the domestic context of services, schema types and service flows in relation to the NextGenPSD2 framework, as well as what constitutes the common core required to implement ÍST TS-313.