Why the IBAN
Satispay connects directly to your bank account (or your prepaid card with IBAN). With Satispay you never have to share your card details when signing up or when making payments.
Why the IBAN code instead of credit/debit cards?
For two reasons: security and efficiency.
We have built Satispay from the IBAN and not from credit/debit cards to make it extremely secure. Satispay connects directly to your bank account and to do this we need to know the unique identifier of your bank account, i.e. the IBAN.
You can use any IBAN from the SEPA countries where the SEPA scheme is available. 
The IBAN is not security-sensitive and, unlike a credit card number, cannot be used to make payments. It can only be debited by financial institutions with a mandate authorised by the account holder.
 All SEPA countries except for: Vatican City, Croatia, Iceland.