The request that initiates a giropay transaction contains fields for the bank code (Bankleitzahl) and account number (Kontonummer). BIC and IBAN may be specified as well.

When a customer wants to initiate a classical domestic bank transfer, the fields BIC and IBAN must be left empty. When a SEPA transfer is initiated, both BIC and IBAN must be specified. In this case, the fields bank code and account number should remain empty. SEPA transactions may only be initiated if the merchant's SEPA account information is stored in the corresponding giropay project of GiroCockpit.

giropay transactions may be initiated with bank code and account number. If BIC and IBAN are also included, this is ignored and a domestic transfer is performed.

giropay transactions should be initiated with BIC and IBAN so that a SEPA transfer can be performed. Specifying the bank code is still possible, though. GiroCheckout will convert the bank code to BIC and initiate a SEPA transfer. If an IBAN is specified (for a possible refund), it is not converted.