aid: principality-building-society url: https://raw.githubusercontent.com/api-evangelist/principality-building-society/refs/heads/main/apis.yml name: Principality Building Society kind: company description: >- Principality Building Society is the largest building society in Wales and the sixth largest in the United Kingdom, founded in 1860 and headquartered in Cardiff. It is a mutual, owned by and run for the benefit of its members rather than shareholders, holding total assets of more than £11 billion and operating around 71 branches and agencies alongside internet and telephone channels. Its product range is deliberately narrow - savings, residential mortgages and investments, plus a commercial lending division - and it does NOT offer current or payment accounts. Principality is authorised by the Prudential Regulation Authority and regulated by the Financial Conduct Authority and the PRA, and is a member of the Building Societies Association. It is NOT one of the nine CMA9 banks mandated to deliver UK Open Banking, and because it holds no payment accounts it falls outside the scope of the PSD2 / OBIE Read/Write (AIS, PIS, CBPII) standard. As of this profile Principality publishes no public developer portal and no confirmed OBIE Open Data API endpoint; the Open Banking API family below is represented as the shared Open Banking Implementation Entity (OBIE) standard for reference only, not as a Principality-operated contract. image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg tags: - Financial Services - Banking - Building Society - Savings - Mortgages - Open Banking - Open Data - PSD2 - OBIE - United Kingdom - Wales - Mutual created: '2026-07-23' modified: '2026-07-23' specificationVersion: '0.19' apis: - aid: principality-building-society:obie-open-data-api name: OBIE Open Data API (Shared Standard - Unverified for Principality) description: >- The UK Open Banking Implementation Entity (OBIE) Open Data API standard - public, unauthenticated reference data covering Branches, ATMs, Personal Current Accounts, Business Current Accounts, Unsecured SME Loans and Commercial Credit Cards. This entry represents the SHARED OBIE standard (Open Data API v1.3); no live Principality Open Data host was confirmed (probes to developer.principality.co.uk and api.principality.co.uk failed to resolve, and /open-banking returned 404). Principality is not a CMA9 bank and is not known to publish these endpoints. The harvested OpenAPI is the OBIE standard, not a Principality contract. humanURL: https://openbankinguk.github.io/opendata-api-docs-pub/v2.4.0/ properties: - type: OpenAPI url: openapi/obie-open-data-swagger.json - type: Documentation url: https://openbankinguk.github.io/knowledge-base-pub/standards/open-data.html - type: APIReference url: https://openbankinguk.github.io/opendata-api-docs-pub/v2.4.0/ - type: SourceCode url: https://github.com/OpenBankingUK/opendata-api-spec-compiled tags: - Open Data - Branches - ATMs - Reference Data - aid: principality-building-society:obie-account-transaction-api name: OBIE Account & Transaction Information API (AIS - Standard, Out of Scope) description: >- The OBIE Read/Write Account and Transaction Information (AISP) standard for reading account, balance and transaction data. FAPI-secured with OAuth2/OIDC, mutual-TLS and PSD2 strong customer authentication. Represented here as the documented OBIE standard only - Principality offers no current or payment accounts, publishes no ASPSP developer portal, and is therefore OUTSIDE the scope of this Read/Write API. No Principality base URL or credentials exist; none are invented. humanURL: https://github.com/OpenBankingUK/read-write-api-specs properties: - type: Documentation url: https://github.com/OpenBankingUK/read-write-api-specs - type: APIReference url: https://openbankinguk.github.io/read-write-api-site3/ tags: - Account Information - AIS - PSD2 - FAPI - aid: principality-building-society:obie-payment-initiation-api name: OBIE Payment Initiation API (PIS - Standard, Out of Scope) description: >- The OBIE Read/Write Payment Initiation (PISP) standard for initiating domestic, scheduled, standing-order, international and file payments. FAPI-secured with OAuth2/OIDC, mutual-TLS and PSD2 strong customer authentication. Represented as the documented OBIE standard only - Principality holds no payment accounts and operates no PISP endpoint, so this is out of scope. No Principality host is fabricated. humanURL: https://github.com/OpenBankingUK/read-write-api-specs properties: - type: Documentation url: https://github.com/OpenBankingUK/read-write-api-specs - type: APIReference url: https://openbankinguk.github.io/read-write-api-site3/ tags: - Payment Initiation - PIS - PSD2 - FAPI - aid: principality-building-society:obie-confirmation-of-funds-api name: OBIE Confirmation of Funds API (CBPII - Standard, Out of Scope) description: >- The OBIE Read/Write Confirmation of Funds (CBPII) standard for confirming whether funds are available on a payment account. FAPI-secured with OAuth2/OIDC, mutual-TLS and PSD2 strong customer authentication. Represented as the documented OBIE standard only - Principality offers no payment accounts and provides no CBPII endpoint. No Principality host is invented. humanURL: https://github.com/OpenBankingUK/read-write-api-specs properties: - type: Documentation url: https://github.com/OpenBankingUK/read-write-api-specs - type: APIReference url: https://openbankinguk.github.io/read-write-api-site3/ tags: - Confirmation of Funds - CBPII - PSD2 - FAPI common: - type: DomainSecurity url: security/principality-building-society-domain-security.yml - type: Authentication url: authentication/principality-building-society-authentication.yml - type: Conformance url: conformance/principality-building-society-conformance.yml - type: ErrorCatalog url: errors/principality-building-society-problem-types.yml - type: LLMsTxt url: llms/principality-building-society-llms.txt - type: Website url: https://www.principality.co.uk/ - type: About url: https://www.principality.co.uk/home/about-us - type: News url: https://www.principality.co.uk/home/about-us/principality-news - type: Support url: https://www.principality.co.uk/home/contact-us/help-and-support - type: TermsOfService url: https://www.principality.co.uk/home/terms-of-use - type: PrivacyPolicy url: https://www.principality.co.uk/home/terms-of-use/privacy-and-security - type: LinkedIn url: https://www.linkedin.com/company/principality-building-society/ maintainers: - FN: Kin Lane email: kin@apievangelist.com