A Certified-Content Letter Is Sent With an Original and Two Copies — The Post Office Proves Only That You Sent It, and You Must Sue Within Six Months of the Demand to Keep the Limitation Period Alive
A certified-content letter, called naeyongjeungmyeong in Korea, is the last document many people send to someone who has not repaid a loan or returned a deposit. But the idea that sending one leaves the other side powerless is only half true. The post office certifies who sent what text and when, and nothing more. It does not vouch that the contents are true. This guide is based on the Enforcement Rule of the Postal Service Act and Article 174 of the Civil Code, checked on October 17, 2026, and explains how to send one and which deadline to track afterward.
What it proves and what it does not
When it accepts the letter, the post office compares the original with the copy and writes on both the date sent, a note that the item is being sent as certified-content mail, and the post office name. So the fact that this text was sent on this date is recorded officially. Whether the other side received it is a separate question. To reduce the chance of a claim that nothing arrived, you can ask for proof of delivery as well. The post office does not judge whether the amounts or claims in your text are correct.
Bring three copies to the post office
Under Article 48 of the Enforcement Rule, anyone sending a certified-content letter submits the original and two copies. The copies must be photocopies of the original. The post office keeps one copy for three years starting the day after mailing and returns the other to the sender. If you do not need a copy, you may submit just one. Since August 2025 the rule also allows an electronic file to be submitted when you send by e-mail.
Format rules to follow
- The paper standard is 210 mm by 297 mm (A4)
- The names and addresses of sender and recipient must be identical on the original, the copy and the envelope
- If you correct the text, write "corrected," "inserted" or "deleted" with the character count in the margin and add a seal or signature
- If there are two or more pages, stamp across the page joints
- The post office will not accept text that violates public order, or an original and copy that a layperson cannot easily tell are the same
The key point is that after acceptance you cannot change names or addresses or correct the text. To avoid a return caused by one wrong character in an address, check it against the registry record or the contract before you go.
If you attach a contract copy or a payment record, the attachment is treated as part of the document. Make the attachments on the original and the copies identical. If you have several recipients and the text is the same, you can send it as a joint certified letter under Article 47, in which case you submit an original for each recipient and two copies listing the names and addresses of all recipients.
What to write so it carries weight
Leave out emotion and set out the facts in order. Give the contract date, the date and amount of the payment, the agreed deadline and the history of your reminders, then end with a specific demand that says what must be done by when. For example, write something like "Return the deposit of the stated amount to the account below by the stated date." You may say that you will take legal action after the deadline, but wording that reads as a threat can be used against you.
Fees depend on the number of pages
The handling fee is calculated by the number of standard-size pages, and writing on both sides counts as two pages. The online post office guide lists 1,300 won for the first page of the copy and 650 won for each additional page. Postage and the registered-mail fee are added, and counter prices can differ, so confirm with the post office before you go.
Why the six months after sending matter
Article 174 of the Civil Code says that a demand alone does not fully interrupt the limitation period. You must file a lawsuit, or seek seizure or provisional seizure, within six months after the demand for it to count. If a claim is close to expiring, mark six months from the mailing date on your calendar and move to the next step, such as a payment order or a lawsuit, before then. The certified letter itself does not pay you the way a court judgment does.
Re-certification and next steps
If you lose your copy, you can ask the post office for re-certification for up to three years after mailing by showing ID and related papers. If the other side does not respond, choose the next step that fits your case. For a lease deposit, see the order for registering the lease. For unpaid wages, see the deadline for substitute payment claims. For a trading fraud, see the account freeze and reporting steps. If you worry about proving that you worked without a written contract, the guide to proof of work may help.
Order of steps
- Organize the facts and your demand on A4 and check the addresses against your documents
- Take one original, two identical copies and your ID to the post office
- If proof of receipt matters, ask for proof of delivery as well
- Mark six months from the mailing date and decide the next step within that time
This article is general information and is not legal advice. If the amount is large or the limitation period is near, consult a lawyer or the Korea Legal Aid Corporation. Sources: Enforcement Rule of the Postal Service Act, Articles 46 to 54; Civil Code Article 174 (National Law Information Center, checked October 17, 2026); online post office guide to certified-content mail.
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