SumUp Germany: API Access & Open Banking Data

SumUp is best known for card readers and merchant payouts, and its business account holds the money your sales generate. If you run a SumUp account in Germany, open-banking.io lets you reach that balance and transaction history through a single, privacy-first connection — no bank certificate, no eIDAS setup, and no data ever leaving your control in readable form. Everything is decrypted on your own device with a key that only you hold.

SumUp is a business-only account (BIC SUMUIE22), so open-banking.io treats it as a commercial connection from the start. A single approval grants up to 180 days of continuous access before SumUp asks you to renew, which keeps reporting and reconciliation running without weekly re-authentication.

How to connect SumUp

Connecting happens entirely inside the open-banking.io dashboard — there is no code, endpoint, or API key involved in this step.

  1. Sign up for open-banking.io and set your encryption passphrase. Your cryptographic keys are generated locally on your device; open-banking.io only ever sees your public key.
  2. In the dashboard, search for SumUp and choose the business account type.
  3. You are redirected to SumUp's own secure login, where you approve access under PSD2 — your credentials go only to SumUp, never to us.
  4. Once approved, your SumUp accounts and transactions sync into your open-banking.io dashboard.

That is the whole flow. You are never asked to redirect anyone, generate a certificate, or paste a key to connect.

Access your data

Reading SumUp data programmatically is an optional step you take after the connection exists. On the Developers page, create an API key and export a credentials.json — this 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 carries the X-Api-Key header, and every response is decrypted locally with your own key. The API key alone only ever returns ciphertext — without your private key, open-banking.io's zero-knowledge servers have nothing readable to give. The CLI and SDK read and sync your existing SumUp connection; they never create one.

All of this runs for around EUR 3 per month.

FAQ

Does SumUp support personal accounts here?

No. SumUp is a business account on open-banking.io, aimed at merchants and companies tracking their payment activity.

How long does one approval last?

Up to 180 days. After that, SumUp prompts you to re-approve access from the dashboard.

Can open-banking.io read my SumUp data?

No. Data is decrypted only on your device with a key you alone hold, so the servers store just your public key.

For merchant reporting that keeps your data yours, start at https://open-banking.io.