Cases eligible for retroactive application
An importer that could not apply for the FTA preferential tariff rate before acceptance of the import declaration may apply for the preferential tariff rate within 1 year of the acceptance date of the import declaration for the goods (Act on Special Cases of the Customs Act for the Implementation of Free Trade Agreements (the "FTA Act"), Article 9 (1)). This is called retroactive application of the preferential tariff rate. Together with the application, you request correction of the tax already paid and receive a refund of the difference.
Retroactive application covers cases where the certificate of origin arrived after the import declaration, where the exporter issued the certificate of origin retroactively, and where the preferential tariff rate was omitted when the import declaration was filed.
Application deadline: 1 year from acceptance, 45 days for a tariff classification change
The general deadline is 1 year from the acceptance date of the import declaration. The period is counted from the acceptance date, not from the import declaration date or the date the certificate of origin was issued.
An importer that did not apply for the preferential tariff rate when filing the import declaration may apply for retroactive application within 45 days of the following dates (Article 9 (2); Enforcement Decree, Article 5 (3)). The Korea Customs Service advises that a case more than 1 year after the acceptance date may also apply within 45 days if it falls under one of these grounds.
- When the tariff classification is changed under Article 87 of the Customs Act and an amended declaration is filed: the date of the amended declaration
- When the head of customs applies a tariff classification different from the one the importer declared and collects duty: the date the payment notice was received
The Act sets this period as "a period within 3 months as prescribed by Presidential Decree", and the Enforcement Decree sets it at 45 days. An importer that already applied for the preferential tariff rate before acceptance or within 1 year of the acceptance date is not subject to this 45-day deadline.
Documents to submit and where to apply
The importer prepares a certificate of origin that is within its validity period. If the importer entrusts the application for the preferential tariff rate and the application for rectification to a Licensed Customs Broker, the Licensed Customs Broker prepares and transmits them.
An importer applying for retroactive application submits to the head of customs the application for the preferential tariff rate with the origin proof documents and the application for rectification under Article 34 (1) of the Enforcement Decree of the Customs Act attached (Enforcement Decree, Article 5 (1)). The Korea Customs Service's Notice on Procedures under the FTA Act requires the following documents to be submitted through the electronic customs clearance system, and allows paper submission if the head of customs recognizes an unavoidable reason (Article 18 (1)).
- Application for the preferential tariff rate (Form No. 1 of the Enforcement Rule of the FTA Act)
- Certificate of origin: Unless the head of customs requires the original, you may submit an electronic image of the scanned original or a copy bearing the "copy of certificate of origin submitted" stamp.
- Application for correction of import and tax declaration stating the content of the application for rectification (Notice on Import Clearance Procedures, Article 48 (2))
- Other origin proof documents: Submit only if the head of customs requires them.
The Korea Customs Service Customer Support Center advises submitting these documents to the tax examination department of the customs office that cleared the goods. If the documents are not submitted, the head of customs may reject the application for the preferential tariff rate (Notice on Procedures under the FTA Act, Article 18 (3)).
Validity period and retroactive issuance of the certificate of origin
The certificate of origin required for retroactive application must be within its validity period as of the import declaration date or the date of application for the preferential tariff rate (Enforcement Decree, Article 5 (2)). If the goods arrived at the port of import before the validity period expired, the period from the day after arrival until the date of application for the preferential tariff rate is excluded from the calculation of the validity period.
The validity period is 1 year from the date of issuance or signature, and the following agreements set it separately (Enforcement Decree, Article 6 (2)).
| Agreement | Validity period |
|---|---|
| United States | 4 years from the date of signature |
| Chile, Canada, New Zealand | 2 years from the date of signature |
| Australia | 2 years from the date of issuance or signature |
| Peru | 1 year from the date of signature (2 years if the goods were temporarily held under the control of the customs authority of a non-party) |
| Vietnam | 1 year from the day after the date of issuance |
| Israel | 12 months from the date of issuance or signature |
When examining the retroactive application documents, the head of customs checks whether the certificate of origin was issued within the retroactive issuance period set by the agreement (Notice on Procedures under the FTA Act, Article 19 (1) 5). The retroactive issuance period and the required wording differ by agreement, and the Korea Customs Service 2025 FTA Frequent Inquiries Case Book gives the following guidance.
- Korea-Singapore FTA: retroactive issuance within 1 year of the shipment date
- RCEP: retroactive issuance within 1 year after the shipment date
- Korea-ASEAN, Korea-China and Korea-Vietnam FTAs: "ISSUED RETROACTIVELY" is entered on the retroactively issued certificate of origin
- Korea-India CEPA: "ISSUED RETROSPECTIVELY" is entered on the retroactively issued certificate of origin
- Korea-EU FTA: an origin declaration may be made after export on condition that it is presented within 2 years after import or within the period stated in the laws of the importing party
Even if an agreement sets a longer period for retroactive preparation, as the Korea-EU FTA does, the deadline for applying for retroactive application in Korea is 1 year from the acceptance date of the import declaration.
Notification of the result and refund
The head of customs that received the application for rectification must notify the requester within 2 months of receiving the request whether the preferential tariff rate applies and whether the tax amount is corrected (Article 9 (5)). If the request is found to be valid after examination, the tax amount is corrected and the difference between the tax paid and the tax payable is refunded (Article 9 (6)).
Articles 46 and 48 of the Customs Act apply mutatis mutandis to the refund. The head of customs decides the customs refund and pays it within 30 days, together with the additional refund interest. If you do not receive notification within the 2 months, you may file an objection, a request for examination, a request for adjudication, or a request for examination under the Board of Audit and Inspection Act from the day after the 2 months end (Customs Act, Article 38-3 (5)).
When origin proof documents were insufficient at import
If you could not obtain a certificate of origin, did not apply for the preferential tariff rate and paid at the general rate, apply for retroactive application within 1 year of the acceptance date after you obtain the certificate of origin. If the exporter could not obtain a certificate of origin before shipment, ask them to obtain a retroactively issued certificate within the period set by the agreement.
The procedure is different if you applied for and received the preferential tariff rate without an issued certificate of origin, or with a certificate of origin under a different agreement.
The Korea Customs Service's "Guidelines on Procedures for Retroactive Application of Preferential Tariff Rates" require you first to pay the shortfall and penalty tax through the supplementary, amended or corrected declaration procedure to cancel the original application for the preferential tariff rate, and then to apply for retroactive application under Article 9 (1). The same procedure applies if you want to switch to a different agreement with a lower rate than the one already applied.
Goods bought directly from overseas
The Korea Customs Service Customer Support Center advises that goods bought through e-commerce that arrived as express cargo and were already charged duty at the general rate may also apply for retroactive application by the same procedure and receive a refund. The Notice on Import Clearance Procedures for Express Shipments requires a person who wants the preferential tariff rate for goods exempt from origin proof to submit to the head of customs a purchase receipt that shows the place of purchase (country) and price information (Article 10 (4)).
What to check before applying
When it receives the retroactive application documents, the head of customs examines the following (Notice on Procedures under the FTA Act, Article 19 (1)).
- Whether the application is within 1 year of the acceptance date of the import declaration, or within 45 days if it is based on a tariff classification change
- Whether the tax amount in the application for rectification is calculated correctly
- Whether the certificate of origin conforms to the form and preparation method of the agreement
- Whether a retroactively issued certificate of origin was issued within the retroactive issuance period set by the agreement
If the certificate of origin has a minor error that does not affect substance such as the origin, like a typographical error, the head of customs does not deny the effect of the document as a whole (Notice on Procedures under the FTA Act, Article 13). If the required documents are not submitted, the head of customs may reject the application (Article 18 (3)).
Source: Act on Special Cases of the Customs Act for the Implementation of Free Trade Agreements, Article 9 (Application for retroactive application of preferential tariff rates), Enforcement Decree of the same Act, Article 5 (Application for retroactive application of preferential tariff rates, etc.), Article 6 (Certificate of origin), Enforcement Rule of the same Act, Form No. 1 (Application for the preferential tariff rate), Notice on Procedures under the Act on Special Cases of the Customs Act for the Implementation of Free Trade Agreements, Article 13 (Minor defects in origin proof documents), Article 18 (Application for retroactive application of preferential tariff rates after acceptance), Article 19 (Examination of retroactive application documents), Customs Act, Article 38-3 (Amendment and correction), Article 46 (Refund of customs refunds), Article 48 (Additional refund interest), Enforcement Decree of the Customs Act, Article 34 (Correction of tax amount), Notice on Import Clearance Procedures, Article 48 (Application for rectification and correction), Notice on Import Clearance Procedures for Express Shipments, Article 10 (Import declaration, etc.), Korea Customs Service Customer Support Center FAQ (retroactive application of preferential tariff rates), Korea Customs Service 2025 FTA Frequent Inquiries Case Book, cases 3, 4, 5, 19 and 21. Checked on October 16, 2026.