Let’s understand sap terminology “House bank, Bank key, Account ID”
Bank is referred as house bank in sap. E.g. HDFC, SBI, ICICI, CITI, BARCLAYS etc.
It’s basically bank branch. Each bank will have several bank branches hence in sap each house bank will have several bank keys. It's alphanumeric number which stores the address of the branch. In India, bank key is equivalent to IFSC code.
Each bank account is created as account ID in sap.
These terminologies are used in configuration for automatic payment program (T code: FBZP) for executing F110.