The simplest possible explanation of the tech behind Üstü Kalsın. No jargon. No fine print.
We use PSD2 Open Banking — the European standard that lets licensed apps (like ours) read your transactions with your consent. We never see your bank password. You can revoke access anytime, from your bank or our app.
After each card payment we compute the difference up to the next złoty (or a larger unit you choose). The total is aggregated locally until it crosses a transfer threshold (5 zł by default).
The accumulated change is sent via SEPA Direct Debit to a licensed CASP partner in the EU. There it is exchanged into your chosen asset (BTC, ETH or USDC). You receive rate and transaction confirmation.
Your assets are held by a MiCA-licensed institutional custodian (BitGo Europe). We use a segregated structure — your funds are accounted for separately from ours. Balance audit available 24/7 in-app.
You can withdraw any time — to your bank account (in PLN) or to your own crypto wallet. Bank withdrawals typically take 1–2 business days.
No. You keep your current bank. Üstü Kalsın runs in parallel, with your PSD2 consent.
Yes. Data is processed only in the EU, GDPR-compliant. We do not sell or share it with third parties.
Revoke consent and withdraw anytime. No penalties, no lock-up.
Basic account — free. Crypto purchase spread: 0.5–1.5%. Premium: 9–15 zł/month for advanced features.
Buying crypto with PLN is not a taxable event. Selling is taxed at 19% (PIT-38). We do not provide tax advice.