Three documents carry an industrial transaction from agreement to delivery. Confusing their roles is what strands shipments at customs and holds payments in a reconciliation queue.
Proforma invoice — the seller's committed offer
Issued by the supplier, it states goods, quantities, unit prices, currency, Incoterm, delivery period, bank details and validity. It is not a demand for payment and not a tax invoice, but it is the document buyers use to raise internal approvals and open letters of credit, and customs authorities frequently use it for pre-clearance valuation.
Purchase order — the buyer's binding instruction
The PO converts the offer into a contract. It should reference the proforma number, repeat the line descriptions verbatim, and attach the buyer's terms — inspection rights, liquidated damages, acceptance basis. A PO that silently changes a line description creates a mismatch that surfaces at invoice stage.
Delivery note — proof of physical performance
It travels with the goods, references the PO, and records batch numbers, packing counts and the receiving signature. For chemicals it should carry batch/lot identifiers that tie back to the certificate of analysis.
The mismatches that stall transactions
- Line description differs between proforma, PO and invoice — payment holds.
- HS code missing or inconsistent — clearance delay.
- Quantity in different units (drums vs kg) across documents.
- Entity name on the invoice differs from the licensed name on the profile.
- No batch reference on the delivery note — QA cannot release the material.
Consistency is a systems problem
These mismatches persist because each document is authored separately in a word processor. Issuing them from one dataset — the approach behind document platforms such as DocMak.com — makes the line description, units and entity details identical by construction rather than by proofreading.
On the buyer's side, document inconsistency is also a vendor verification signal worth reading carefully.