Open item management

Compiere is, by default, an open item management system. This means that customer invoices and receipts (Sales Cycle) and purchasing invoices and payments (Payment Cycle) need to be allocated in order for the open balance on a document to be correctly reflected. Account statements are thus shown for the document on an open amount basis and not on a balance brought forward basis. Thus, in terms of accuracy of open amounts on documents, this requires discipline in the accounts department and also from customers and vendor reconciliations in order to reflect the correct statement of account at any given time. If this is not practical then an automated oldest invoice allocation process can be followed, but unless this is normal business practice in your industry or region, it is suggested that it is legally agreed with your customer.

Capturing a receipt from a customer or payment to a vendor is done through the Payment window:

Allocating receipts or payments to invoices...