External transactions must be assigned to a posting rule in electronic bank statement Customizing. The system uses the posting rule to determine which bank or subledger accounts to post to.

Posting rules are represented in the system by a non bank-specific code (for example, 0001 for debit memos).

As banks have many different transactions that result in the same kind of postings in bank accounting, you require an internal code for electronic bank statement Customizing that is linked to a posting rule. The posting rule does not have a direct link with the external transaction.

From the point of view of financial accounting, all these examples of external transactions lead to the same posting. Consequently, you have to assign them to the same posting rule (for example, 0001 for debit memo). The system recognises how to post a debit memo based on the posting rule.

Using non bank-specific codes (posting rules) in Customizing for the electronic bank statement has the advantage that you only need to determine how a transaction (for example, debit memo) is posted once, and not three times.

For more information on Customizing settings for posting rules, see the SAP Solution Manager documentation.