C24 Open Banking & API Access via open-banking.io

C24 is Germany's fully digital smartphone bank, and open-banking.io gives you a private, standards-based way to reach the balances and transactions behind your C24 account. Instead of scraping screens or juggling bank certificates, you authorise access once under PSD2 and let your data flow into a dashboard that only you can decrypt. C24 supports both personal and business accounts, and each consent you grant stays valid for up to 180 days before a quick re-approval.

How to connect C24

Connecting happens entirely inside 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 keys are generated locally on your own device, so no one else can read what comes back.
  2. In the dashboard, pick C24 from the bank list and choose the account type you want, personal or business.
  3. You are redirected to C24's own secure login (BIC DEFFDEFF), where you approve the access request on the bank's consent screen.
  4. Your C24 accounts sync straight into your open-banking.io dashboard, ready to view.

That is the whole flow: you stay on C24's trusted pages for authentication, and open-banking.io never sees your login details.

Access your data

Reading C24 data programmatically is an optional step you take after the account is already connected. Open the Developers page, create an API key, and export a credentials.json bundle that pairs that key with your private decryption key. From there you can run the CLI (openbanking accounts, openbanking transactions, openbanking sync), call the REST API, or use an SDK. Requests carry your key in the X-Api-Key header, and every response is decrypted locally with your own key — the servers only ever hold ciphertext and your public key.

FAQ

Does open-banking.io store my C24 password?

No. You authenticate directly on C24's own login and consent screens. open-banking.io is zero-knowledge and certificate-free, holding only your public key.

Can I connect C24 from the CLI or an SDK?

No. Connecting is a dashboard-only action. The CLI, SDK, and REST API read and sync accounts you have already connected — there is no connect command.

How much does it cost?

Around EUR 3 per month for open-banking.io, covering access to C24 and 2,600+ other EU and UK banks.

Ready to start? Connect your C24 account at open-banking.io.