Union-Bank API Access & Open Banking Integration

Reaching your Union-Bank account data no longer means wrestling with eIDAS certificates or a bespoke PSD2 sandbox. open-banking.io gives you a single, privacy-first path to your Union-Bank balances and transactions — covering both business and personal accounts — and does it without ever being able to read what it moves. With more than 2,600 European banks on one platform, Union-Bank (BIC UNBNDE21XXX) slots in alongside the rest of your financial stack.

The key difference is where decryption happens. Your encryption keys are generated on your own device from a passphrase only you know. open-banking.io holds nothing but your public key, so everything that syncs is opened locally — a genuine zero-knowledge design.

How to connect Union-Bank

Connecting is done entirely in the open-banking.io dashboard — there is no API call, code, or key involved in this step:

  1. Sign up for open-banking.io and set your encryption passphrase. Your private key is created locally on your device at this moment.
  2. In the dashboard, search for and select Union-Bank, then choose the account type you want to link (business or personal).
  3. You are redirected to Union-Bank's own secure login, where you approve access on the bank's PSD2 consent screen.
  4. Once approved, your Union-Bank accounts sync straight into your dashboard, ready to view.

Your PSD2 consent stays valid for up to 180 days, after which you simply re-approve on Union-Bank's screen to keep the data flowing.

Access your data

Want to work with the data in code? That is an optional step you take after the bank is connected. On the Developers page, create an API key and export a credentials.json file, which bundles the API key together with your private decryption key. From there you can use the CLI (openbanking accounts, openbanking transactions, openbanking sync), an SDK, or the REST API directly.

Every request authenticates with the X-Api-Key header, and every response is decrypted locally with your own key. An API key on its own only ever returns ciphertext — without your private key, there is nothing readable to see.

All of this runs on a flat plan of roughly EUR 3/month.

Do I need a certificate or developer account with Union-Bank?

No. open-banking.io is certificate-free; you approve access on Union-Bank's own consent screen and nothing more.

Can open-banking.io read my Union-Bank transactions?

No. It stores only your public key, so data is decrypted solely on your device.

Can the CLI connect my Union-Bank account?

No. The CLI and SDK only read and sync connections you have already made in the dashboard — there is no connect command.

Start at open-banking.io.