When a Korean Customer Won’t Pay: Demand Letter, Payment Order, or Lawsuit — Where to Start

When a Korean customer stops paying invoices, foreign companies often face an unfamiliar choice of tools. A Korean lawyer may suggest a certified demand letter, a court payment order, a lawsuit, or a provisional attachment of the debtor’s assets. Each tool serves a different purpose, and the best sequence depends on two questions: whether the debtor disputes the debt, and whether it is likely to move or dissipate its assets. This article explains the main options under Korean law and how to combine them.

1. Start with Three Questions

Before choosing a tool, answer three questions:

• Is the debt disputed? A customer that admits the debt but cannot or will not pay calls for a different approach from one that claims the goods were defective or the services incomplete.
• Is there a risk that assets will disappear? If the debtor is in financial difficulty, transferring assets to related parties, or closing its business, speed matters more than cost.
• What does the contract say? The governing law, jurisdiction, and any arbitration clause determine where and how you can sue. The applicable limitation period sets the deadline.

2. The Certified Demand Letter

A certified demand letter is sent through Korea Post, which keeps a copy and certifies the content and the date of delivery. It is usually the first step.

What it does:

• Proof. It creates official proof that you demanded payment, and of what you demanded.
• Default. It can put the debtor in default where no payment date was fixed, so that default interest starts to run. Under Korean commercial law, the default rate is generally 6% per year unless the contract provides otherwise.
• Contract notices. It can serve as formal notice of termination or of a cure deadline under the contract.
• Limitation period. It temporarily interrupts the limitation period. The interruption is effective only if you begin court proceedings, such as a lawsuit, payment order, or provisional attachment, within six months.

What it does not do: A certified letter has no enforcement power. A debtor that ignores it suffers no direct legal consequence.

When to skip it: If there is a real risk that the debtor will move its assets once it learns you are pursuing the debt, consider filing a provisional attachment first. A demand letter can give the debtor advance warning.

Key takeaway: A certified letter, ideally sent by Korean counsel, is cheap and often prompts payment. Do not rely on it to stop the limitation period for more than six months.

3. The Payment Order

A payment order is a simplified court procedure for monetary claims. The court reviews the application and supporting documents, such as the contract, invoices, delivery records, and correspondence, without a hearing. It then issues an order directing the debtor to pay.

How it works:

• Filing. The creditor files the application, which can be done electronically, with the court for the debtor’s address. The court fee is one-tenth of the fee for an ordinary lawsuit.
• Service. The court serves the order on the debtor. It must be served at an actual address in Korea. A payment order cannot be served by public notice, so it does not work against a debtor that cannot be located.
• Objection. The debtor has two weeks from service to file an objection.
• No objection. The order becomes final and has the same effect as a final judgment. You can then enforce it against the debtor’s assets.
• Objection filed. The case automatically becomes an ordinary lawsuit. You have lost little, because the case continues in court and the fee paid is credited.
• Statutory interest. From the day after service, statutory interest under the Act on Special Cases Concerning Expedition of Legal Proceedings, generally 12% per year, can be claimed on the unpaid amount.

When it works best: The debt is clear and documented, the debtor has a known business address in Korea, and you do not expect a genuine defense. Many debtors that are simply delaying payment do not object.

Key takeaway: For an undisputed debt, a payment order is usually the fastest and cheapest way to obtain an enforceable title. If the debtor objects, you are in the same position as if you had sued.

4. A Lawsuit, Including Small Claims

If the debtor disputes the debt, for example by alleging defects, set-off, or a different agreement, it will almost certainly object to a payment order. Filing a lawsuit directly is then more efficient.

• Small claims. Claims of KRW 30 million or less are heard under the Small Claims Trial Act, with simplified procedures and usually faster hearings.
• Ordinary lawsuits. A first-instance judgment typically takes several months to a year, depending on the complexity of the dispute.
• Security for costs. A foreign plaintiff without a domicile or office in Korea may be ordered, at the defendant’s request, to provide security for the defendant’s litigation costs.
• Evidence. Documents in foreign languages must be submitted with Korean translations. Prepare a clear record of the contract terms, orders, deliveries, invoices, and payment history early.
• Interest. Once the complaint is served, statutory interest generally runs at 12% per year until payment.

5. Freezing Assets First: Provisional Attachment

A provisional attachment is a court order that freezes the debtor’s assets before you obtain a judgment, so that they remain available for enforcement. The debtor is not notified before the order is issued.

• Targets. These are typically bank accounts, receivables from the debtor’s own customers, real estate, and vehicles.
• Requirements. You must show a prima facie claim and a need for preservation, such as deteriorating finances, asset transfers, or business closure.
• Security. The court usually requires the creditor to provide security. This is often satisfied with a guarantee insurance policy, with part in cash for some asset types.
• Speed. Orders can be obtained within days to a few weeks.
• Practical impact. Freezing a debtor’s bank account or its receivables from major customers often leads to immediate settlement negotiations.
• Main action. After the attachment, you must pursue the claim through a payment order, lawsuit, or arbitration. The debtor can ask the court to order you to do so within a deadline.

Key takeaway: If there is any sign that the debtor’s assets may disappear, file a provisional attachment before sending demands or starting the main action.

6. If Your Contract Has an Arbitration Clause

If the contract requires arbitration, for example under the KCAB, ICC, or SIAC rules, the debtor can object to a Korean court action on that basis. The court will dismiss the lawsuit. A payment order is also likely to be met with an objection and an arbitration defense.

Two points remain important:

• Provisional relief. Korean courts can still grant provisional attachments and other interim measures in support of arbitration.
• Enforcement. An arbitral award must be recognized and enforced in Korea through a court procedure. This is generally available for awards from New York Convention countries.

7. Limitation Periods: The Deadline Foreign Creditors Miss

If Korean law governs the claim, the limitation period may be shorter than expected:

• Commercial claims. These are generally subject to a five-year limitation period.
• Sale price of goods sold by merchants. This is subject to a short three-year limitation period under the Civil Code. Some service fees are also subject to short periods.
• Interest claims. Claims for interest paid periodically may also have short periods.
• International sales. Where the UN Convention on Contracts for the International Sale of Goods applies, it does not govern limitation periods, so the period is determined by the applicable national law.

Check the limitation period as soon as payment stops. Remember that a demand letter interrupts it only temporarily.

8. From Judgment to Payment: Enforcement

A final judgment or final payment order allows you to enforce against the debtor’s assets. You can:

• seize bank accounts and receivables
• auction real estate and movable property
• use asset disclosure orders and court asset searches where the debtor’s assets are unknown

These procedures are explained in our separate article on tracing hidden assets in Korea.

If the debtor enters rehabilitation or bankruptcy proceedings, individual enforcement is generally stayed. You must file your claim in the insolvency proceedings within the court’s deadline.

9. Choosing the Sequence

Situation	Recommended first step	Next step
Debt undisputed, debtor solvent, known address	Certified demand letter	Payment order
Debt undisputed, risk of asset flight	Provisional attachment	Payment order or lawsuit
Debt disputed	Demand letter, optional	Lawsuit (small claims if KRW 30 million or less)
Debt disputed, risk of asset flight	Provisional attachment	Lawsuit
Arbitration clause in contract	Demand letter, plus provisional attachment if needed	Arbitration, then enforcement of the award
Debtor cannot be located	Asset and address investigation	Lawsuit, since public-notice service is available in a lawsuit but not for a payment order
Debtor in insolvency	—	File the claim in the insolvency proceedings

10. Conclusion

In Korea:

• A certified demand letter is a sensible first step for most unpaid invoices, but it cannot compel payment.
• A payment order is the fastest route for undisputed debts.
• A lawsuit is better where the debtor has a genuine defense.
• A provisional attachment should come first whenever there is a risk that assets will disappear.

Checking the limitation period and the contract’s dispute resolution clause at the outset avoids the most common mistakes.

Key takeaway: Match the tool to the debtor. Use speed and asset freezing where recovery is at risk, and the low-cost payment order where the debt is clear.