# Tandem Bank

**Canonical:** https://apis.io/providers/tandem-bank/  
**Website:** https://www.tandem.co.uk/  
**APIs profiled:** 3

Tandem Bank (Tandem Bank Limited) is a UK app-only challenger and self-styled "greener" digital bank founded in 2014 and headquartered in Blackpool, England, with offices in Cardiff, Durham, and London. It obtained its UK banking licence through the 2018 acquisition of Harrods Bank and has since grown by acquiring Allium Lending Group, Oplo, and Loop Money, offering savings and cash ISAs, green home-improvement and home loans, mortgages, motor finance, and a credit card. Tandem Bank Limited is authorised by the Prudential Regulation Authority and regulated by the Financial Conduct Authority. It is not one of the CMA9 and does not publish a public Open Data reference API; as an FCA-authorised ASPSP it meets UK Open Banking / PSD2 obligations through a dedicated interface provided by Token, conformant to the Open Banking Implementation Entity (OBIE) Read/Write Standard for Account and Transaction Information (AIS), Payment Initiation (PIS), and Confirmation of Funds (CBPII), secured with FAPI-grade OAuth2/OIDC, mutual-TLS, and PSD2 strong customer authentication. Tandem also consumes Open Banking as a TPP via TrueLayer for savings onboarding and transfers.

## Kin Score — 39.0 / 100 (thin)

Scored 2026-08-20 under rubric 0.12.0. Trend: flat (+0.0 from 39.0).

| Facet | Score |
|---|---|
| Discoverability | 72.2 |
| Contract Quality | 55.9 |
| Governance | 16.7 |
| Contract Governance | 16.7 |
| Operational Transparency | 0.0 |
| Developer Ergonomics | 42.3 |
| Commercial Clarity | 10.5 |
| Access Clarity | 10.5 |

Regulatory layer — **Banking & Open Finance**: 65.8 (matched via tags).

## Agent readiness — 40.4 (agent-ready)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | no |
| MCP Server | no |
| Auth Clarity | yes |
| Idempotency | documented |
| Error Semantics | documented |
| OpenAPI Examples | no |
| Rate Limit Signal | verified |
| Event Surface Described | no |
| Agent Skills | derived |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |

## APIs (3)

- **Tandem Bank Account and Transaction Information API (AIS)** — Tandem Bank's Open Banking Account Information Service (AIS) exposing account, balance, transaction, and product data for its credit card and savings products. Delivered through...
- **Tandem Bank Payment Initiation API (PIS)** — Tandem Bank's Open Banking Payment Initiation Service (PIS) for initiating domestic and other payments against Tandem accounts. Delivered through Tandem's PSD2 dedicated interfa...
- **Tandem Bank Confirmation of Funds API (CBPII)** — Tandem Bank's Open Banking Confirmation of Funds Service (CBPII) allowing card-based payment instrument issuers to confirm the availability of funds. Delivered through Tandem's ...

## MCP servers (1)

- **Tandem Bank MCP Server**

## Agentic access (1)

- **Tandem Bank Agentic Access** — 74 operations · 20 acting

## Security (2)

- **Tandem Bank Authentication** — oauth2 · 2 schemes
- **Tandem Bank Domain Security** — TLSv1.3 · HSTS · DMARC

## Tags

Financial-Services, Banking, Open Banking, PSD2, OBIE, FAPI, United Kingdom, Payments, Account Information, Challenger Bank, Fintech

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/tandem-bank/). Scores are computed from the provider's own public artifacts under a published rubric.