ING Bank

ING's Open Banking API provides PSD2-compliant access to banking services with both Premium and PSD2 APIs.

OAuth2 authentication is combined with mTLS and HTTP signature signing for enhanced security. The API covers account information, payment initiation, and confirmation of funds extensively. It includes comprehensive SDKs and sandbox environment with test data. However, production access requires PSD2 registration with a National Competent Authority and eIDAS certificates. Complex authentication flow with multiple certificate requirements.

Ideal for fintech applications needing regulated banking access in Europe with strong security requirements.