Customized invoicing processes can be defined along with invoicing processes delivered by SAP. SAP invoicing program behaviour can be adjusted according to the requirements.

Invoicing processes are used as selection parameters for mass activities of "Invoicing in Contract Accounts Receivable and Payable". Invoicing documents number ranges are defined and dependent on the invoicing processes. Invoicing processes are differentiation characteristic for the activation of optional invoicing functions.

The individual process steps of "Invoicing in Contract Accounts Receivable and Payable" are described as follows: -

• Data Selection - The invoicing orders are selected for the invoicing process. Selection criteria can be defined for the data selection of the invoicing process.
• Creation of Invoicing Units - The system groups the selected invoicing orders into invoicing units for each contract account. Several invoicing units can be created for each contract account. For each invoicing unit, "Invoicing in Contract Accounts Receivable and Payable" creates one invoicing document. Creating the invoicing units based on the criteria defined for the invoicing process.
• Processing of Billing Documents - The selected billing documents of an invoicing unit are included in the invoicing document. The billing document items are linked with the items of the invoicing document and the derivations required for the posting in Contract Accounts Receivable and Payable (FI-CA) are performed.
• Performance of Additional Functions – In "Invoicing in Contract Accounts Receivable and Payable", further functions can integrate of FI-CA. You define which additional functions are performed for each invoicing process.
• Account Maintenance - Using the account maintenance integrated in "Invoicing in Contract Accounts Receivable and Payable", you can perform clearing between the posting documents entered in invoicing and the open items of the contract account posted before invoicing. You define the criteria for clearing in the clearing control.
• Update - The invoice document created for the invoice unit and the posting documents are written to the database. The processed invoice orders are deleted. Along with the invoicing unit, a correspondence container for invoice printing and an extraction order for the update to BW are also created.