Recovering unpaid invoice across borders is rarely a single legal step. It is a sequence of decisions: whether the debt is real, whether the buyer can pay, and which route is worth the cost of pursuing it. This page sets out how the claim is built, what evidence carries weight, and when the honest answer is to stop.
The pattern repeats across sectors. A seller in one country delivers goods or performs a service for a buyer in another. The invoice falls due, a reminder goes unanswered, and the file lands on a desk months later with no clear next step. Sometimes the buyer is genuinely insolvent. More often the buyer is solvent and simply managing cash by not paying the creditor who pushes least.
This pattern sits at the centre of cross-border debt recovery: a counterparty that has stopped responding, a contract that may or may not specify a court or an arbitral seat, and a creditor who needs to know within days, not months, whether pursuing the balance makes commercial sense.
An unpaid invoice claim stands or falls on paper that exists before the dispute starts, not on paper produced afterward. We look for the contract or purchase order that fixed price and terms, the invoice that matches those terms, and proof that goods were delivered or services performed as agreed. A signed delivery note, a bill of lading, an acceptance email or a project sign-off carries more weight than any later explanation.
Correspondence matters as much as the invoice itself. A buyer who acknowledges the debt in writing, even while asking for time, has conceded the point that later defences try to unwind. Silence, by contrast, is neutral. It tells us nothing about the merits, only that the file needs a formal step to move it forward.
Three defences appear repeatedly. The buyer claims the goods or services were defective. The buyer claims the invoice does not match the agreed price. The buyer claims a set-off against a separate contract with the same seller. Each of these can be genuine, and each can also be a stalling tactic raised only once payment is chased.
Timing defeats a weak version of any of these defences. A quality complaint raised for the first time after the payment reminder, with no earlier inspection report or rejection notice, is difficult for a buyer to sustain. A buyer who resists one invoice on manufactured grounds often resists a related one on the same basis, including unpaid freight invoices tied to the same shipment, which is worth checking before any single claim is framed in isolation.
The route starts with assessment, not with a letter. We review the documents, identify which court or arbitral forum has jurisdiction under the contract or under the applicable default rules, and set out realistically what recovery would cost against what is at stake. That review is the point of a claim assessment report, and it is the only sensible starting point on a claim that has not yet been tested.
If the assessment supports moving forward, the next step is usually a formal payment demand issued through pre-legal collection in the debtor's own jurisdiction, since a demand carrying local legal weight is read differently from a reminder sent by the creditor itself. Where the contract or the applicable framework points to arbitration, instruments such as the New York Convention (1958) support recognition of the award once it is made. Within the European Union, Regulation (EU) 1215/2012 (Brussels I Recast) governs which court has jurisdiction and how a judgment moves between member states. Cross-border sale of goods contracts frequently fall under the United Nations Convention on Contracts for the International Sale of Goods (CISG, 1980) unless the parties have excluded it. None of this replaces litigation or arbitration if the buyer still refuses to pay; it only determines where the case belongs and what happens to a judgment or award afterward, including enforcement of a foreign judgment once one exists.
Any one of these criteria is enough to close the file at the assessment stage. We say so directly rather than opening a matter that has no realistic prospect of return.
A matching contract or purchase order, the invoice itself, and proof of delivery or performance form the core. Written acknowledgement of the debt from the buyer strengthens the position further.
It depends on whether the buyer responds to a formal demand, whether the contract specifies a forum, and which country's court or arbitral process applies. We give a realistic timeframe for the specific claim once the assessment is complete, rather than a general figure.
Sometimes, if the buyer is solvent and a formal demand alone is likely to produce payment. It is rarely worth pursuing through litigation once the legal cost approaches the value of the invoice, which is exactly what the assessment is designed to establish before any commitment is made.
The invoice sitting unpaid does not become easier to recover the longer it waits, and the shipment or service behind it cannot be undone once the dispute hardens. The real risk on a file like this is not the debt itself but choosing a recovery route before anyone has tested whether it fits the facts.