Three-Way Matching Was Designed for Standard AP. Maritime Is Not Standard.
What four-way matching is, why three-way matching falls short for maritime invoice control, and how vessel confirmation changes what gets paid.
By Errikos Andreakos
Chief Commercial Officer for MarTrust
This article is part of our series on how to close the control gap in maritime's procure to pay workflow (article four of seven)
What is four-way matching in maritime procurement?
Four-way matching validates four documents before payment is released: the purchase order, the supplier's delivery note, the invoice, and a vessel confirmation of receipt. Standard three-way matching compares only the first three. The fourth check catches discrepancies between what the supplier says was delivered and what the vessel actually received, discrepancies that three-way matching clears before the vessel has had a chance to verify.
A deck stores delivery arrives at the berth. The chief officer signs the supplier's delivery note while the vessel is preparing to depart. The invoice arrives the following day, matches the delivery note, and clears. Three days later, at sea, the bosun completes the stores inventory. Three line items are short.
Standard three-way matching has already paid the full invoice.
Why three-way matching breaks down in maritime
Three-way matching compares three documents: the purchase order, the supplier's delivery note, and the invoice. If the three agree within tolerance, the invoice clears. For most industries, that is a sufficient control. In maritime stores and provisions deliveries, there is a gap.
The delivery note is signed at the berth. The chief officer signs to acknowledge that goods arrived at the vessel. That signature does not always mean the goods matched the order in full. The vessel is preparing to depart. There is no time and no practical way to verify every line item before the supplier's driver leaves. The signature is correct as far as it goes. It does not confirm delivery as invoiced.
SpecTec's 2026 research across operators managing 3,150 vessels found three-way matching failing between 60 and 70 percent of the time in maritime. The cost per failed match: $85 in staff time. Large fleet operators process 25,000 purchase orders a month. The arithmetic of that exception rate runs to millions of dollars annually in administration that produces no commercial value.
Learn how your team can scale invoice management with the fleet without adding to headcount
Closing the invoice control gap in maritime
Why vessel confirmation is the missing piece of the invoice matching puzzle
Four-way matching adds a fourth document: vessel confirmation of receipt. The invoice cannot clear until the ship confirms what it actually received. When the bosun's inventory shows three short lines, those lines are flagged before payment rather than after. The supplier is queried while the invoice is still open. The credit note conversation never starts because the payment does not go out in full until the vessel's confirmation agrees with the invoice.
Credit note recovery is slow. The supplier holds a signed delivery receipt. They have no incentive to move quickly. The AP team spends time managing a recovery process for a transaction that has already settled. Building vessel confirmation into the clearing process removes that chase entirely. It becomes a prerequisite for payment, not a follow-up.
The Maritime Control Gap covers the vessel confirmation scenario in full, alongside the other situations where standard matching logic reaches its limits.
Find out why leading ship managers are using Marcura to streamline their entire procure to pay process
Take control of your procure to pay workflow
Read more
recent news
New guide
Take control of Procure-to-Pay
Why invoice control breaks down between PO and payment — and how leading ship managers close the gap. Free guide, plus two diagnostic tools.
