Quantity Variance
The difference between the quantity delivered and the quantity invoiced for goods received on a purchase order is the open quantity. A quantity variance exists if the quantity you are entering from the invoice does not match this open quantity.
The SAP system allows the following quantity variances:
The quantity listed in the invoice can be larger or smaller than the quantity still to be invoiced. If it is smaller, a further invoice for the remaining quantity is expected. If it is larger, a further goods receipt will be expected for the extra quantity charged.
When goods-receipt-based Invoice Verification is active, an invoice can only be posted when at least one goods receipt hsa been posted for the order item. In the standard system, the quantity invoiced cannot be larger than the quantity expected by the system for invoicing, since further invoices can be received for a goods receipt, but not further goods receipts. You can, however, configure the message as a warning, thus allowing you to post the invoice.