Track the portion used against each PO
The sample PO-01 limit is A$5,000. Issued allocations of A$1,800 and A$1,700, less an entered A$100 credit, leave A$1,600. The draft A$500 against PO-02 is excluded. A remaining limit is a mathematical check against the figures supplied; it does not authorise another A$1,600 invoice.
Split cross-PO invoices explicitly
If one invoice covers two purchase orders, use a distinct allocation entry for each portion. Do not paste the whole invoice total against both POs. Keep entry IDs unique and reconcile the portions with the original document. Credits must have a real supporting record. The checker rejects a reference that has no matching PO instead of silently creating a new limit.
Check approval, delivery and tax basis separately
Use the same currency and consistent tax basis for limits and allocations. A balance can be positive while the next stage is not delivered or approved. Review the purchase order, changes and customer requirements before creating the next invoice. This page does not synchronise procurement software, change a PO or update an invoice status.
Keep a review record
Run the check again whenever an input changes. Invalid or incomplete input clears the previous live result and disables download, so an old answer is not presented as current. Downloads contain the check table only; they are not a tax invoice, payment receipt or successful invoice export. They do not update drafts, history, login or payment status.
business.gov.au: invoice preparation and references · Reference for the underlying recordkeeping or calculation concept; not an endorsement of this helper.