When an HS code could go two ways, budget the tax and the schedule first
This calculator is based on Korean rules for 2026: the Customs Act, its Enforcement Decree and Rule, and the Korea Customs Service notice on classification review, as checked on 2026-10-24.
It is a Korea-specific planning estimate, not a classification decision, a customs assessment or a clearance-date guarantee.
When you import a product for the first time, a customs broker often says it could fall under heading A or heading B.
If the duty rate changes from 0% to 8% depending on the classification, both the import budget and the selling price move with it.
Budgeting on the lower rate as if it were final can mean paying the shortfall, interest and penalties all at once when the higher rate is confirmed later.
An HS advance ruling lets the Korea Customs Service, through its Customs Valuation and Classification Institute, fix the HS heading of the goods before the import declaration.
Once you have the ruling, Customs must apply that classification to the same goods, so the rate uncertainty disappears, but shipment or launch may be delayed while you wait.
The calculator combines the duty and import VAT range across the candidate classifications your broker named with the processing period, analysis fee and waiting cost, and shows how much cash to prepare for each import schedule.
Who this is for
- Small importers who cannot set a budget because brokers give different HS codes for a new product or supplier
- Businesses deciding whether to request a ruling and absorb storage and launch delay while waiting
- Importers who must bring in the first shipment before the ruling and want to know the possible extra tax in advance
- Staff preparing candidate rates, timelines and documents before meeting a customs broker
The Korean HS advance ruling system at a glance
Customs Act Article 86 allows a request to the Commissioner of the Korea Customs Service to review the tariff classification before the import or export declaration.
Under Article 2 of the notice on classification review and operation, the request is filed electronically through UNI-PASS with the head of the classification institute and takes effect when a receipt number is assigned.
Filing limits, processing periods and fees for an advance ruling and a re-review| Item | Advance ruling | Re-review | Basis |
|---|
| Filing limit | Before the declaration | Within 30 days of the notice | Act Article 86(1) and (3) |
| Processing period | 30 business days (15 if expedited) | 60 business days | Decree Article 106(4) and (7), Notice Article 14 |
| Correction request period | Up to 20 days | Up to 20 days | Decree Article 106(2), Notice Article 5 |
| Analysis fee | KRW 30,000 per item | KRW 30,000 per item | Rule Article 33, Notice Article 13 |
| Number of requests | Repeat requests may be rejected | Once | Rule Article 33-2, Notice Article 3 |
Processing periods count business days, including the first day and excluding Saturdays and public holidays (Civil Petitions Act Article 19(2)), and leave out correction, analysis, committee review, World Customs Organization queries, technical advice and hearing time.
A ruling stays valid until changed under Article 87, and Customs applies the notified classification to the same goods (Act Article 86(5) and (7)).
The application states the name, specification, manufacturing process, origin, use, intended customs office and reason, and comes with a sample and other explanatory material (Decree Article 106(1)).
Article 2 of the notice also asks for the manufacturer’s composition sheet, process flow chart and specification, a description of use and, for machinery, the names, functions and operating principle of the components.
If material is missing, Customs requests a correction within a period of up to 20 days, and an application can be rejected if a second correction request is ignored.
Processing time is counted in business days and fees per item
Expected notice date
The calculator adds the expected correction and analysis time in calendar days to the filing date, treats that day or the next business day as day 1, and shows the 30th business day (15th for expedited review) as the expected notice date.
It skips Saturdays, Sundays and Korean public holidays, substitute holidays and election days for 2026 and 2027.
The result is an approximation that can differ by a day or two depending on when the excluded periods actually occur.
Ruling costs
Goods that need analysis pay KRW 30,000 per item before analysis begins, and the fee is not refunded after analysis even if the application is rejected (Notice Article 13).
A broker’s fee and the VAT on it are added if you use one, and a general VAT taxpayer recovers that VAT as input tax.
If you do not know whether analysis is needed, the calculator includes the fee and analysis time conservatively.
- Expedited review applies only when a reason listed in Article 14(1) of the notice is accepted, such as an imminent declaration, a severe economic loss from delay, or origin verification requested by a foreign customs authority under an FTA.
- Include only confirmed amounts in the daily waiting cost, such as bonded storage quotes, contribution lost to a delayed launch, or substitute sourcing.
- The import-ready date adds the follow-up days needed after the notice, and waiting cost accrues for each day it falls after your planned import date.
Duty and import VAT for each candidate classification
Duty = customs value × candidate duty rate (amounts below KRW 10 dropped)
Import VAT = (customs value + duty) × 10% (amounts below KRW 10 dropped)
The customs value is the price of the goods plus freight and insurance to the Korean port, converted at the Customs exchange rate.
Under VAT Act Article 29(2) the import VAT base is the customs value plus duty and excise-type taxes, and fractions below KRW 10 are dropped under National Treasury Funds Management Act Article 47.
- For each candidate, enter the rate that would actually apply, as confirmed by your broker: the basic rate, the WTO concession rate, an FTA preferential rate or a quota rate.
FTA rates require proof of origin and the related conditions.
- A difference in duty rate also flows into import VAT at 10%.
For example, a KRW 4,000,000 duty gap becomes a KRW 4,400,000 gap in total tax.
- General VAT taxpayers recover import VAT as input tax, so it must be prepared as cash but is excluded from economic cost.
Simplified and VAT-exempt businesses and individuals treat VAT as cost.
- Individual consumption tax, liquor tax, education tax and anti-dumping duties are not calculated, so check them separately if they apply.
Three import paths compared on the same basis
The calculator never assigns probabilities to the candidates; it computes the amount for each possible ruling and shows the minimum to maximum range.
Using the same candidate list for three import paths lets you see the trade-off between time and cash side by side.
1. Import after the ruling
You declare under the ruled classification after the expected notice date.
Rate uncertainty disappears, but storage and launch delay accrue for the waiting days, and the analysis and broker fees are added.
Cash to prepare equals the ruled candidate’s tax plus ruling costs plus waiting cost.
2. Apply, then import before the ruling
You file the request and import on the planned date under the candidate you would declare.
If the ruling carries a higher rate, you pay the difference with interest or penalties by correction or amended declaration; if it is lower, you claim a refund.
The biggest risk is that declaring the same goods during the review can lead to rejection of the application.
3. Declare without a ruling
You import under the declared candidate and never request a ruling.
If Customs later reassesses to another candidate, the shortfall carries a 10% under-declaration penalty and a late-payment penalty of 0.022% a day.
The calculator shows only the maximum exposure on this path, never a saving.
If the ruling differs after an early import: correction or amendment
The Customs Act settles a shortfall differently depending on when it becomes known.
The calculator treats the expected notice date plus your follow-up days as the settlement date and applies the rules below.
Extra burden under correction, amendment, reassessment and refund claims| Settlement | When it applies | Interest or penalty rate | Extra burden |
|---|
| Correction (Article 38-2) | Within six months of declaration and payment | 3.1% a year | Shortfall plus correction interest from the day after the due date to the correction date |
| Amended declaration (Article 38-3) | After the correction period | 0.022% a day | Shortfall plus a late-payment penalty; the 10% under-declaration penalty is relieved if filed within two months of the ruling notice (Article 42-2(1)(7)) |
| Customs reassessment (Article 38-3(6)) | Customs finds the error after a declaration without a ruling | 10% + 0.022% a day | Shortfall plus the under-declaration and late-payment penalties (Article 42) |
| Refund claim (Article 38-3(2)) | The ruled rate is lower; within five years of the first declaration | Not applicable | Refund of the excess (refund interest not included) |
Check before importing early
Enforcement Decree Article 106(3)(2) lists, as a ground for rejection, the case where the applicant has already declared goods identical to those under review.
If an early import gets the application rejected, the rate uncertainty remains and you carry the same risk as the no-ruling path.
If the planned import date precedes the filing date, the request does not meet the before-declaration requirement and the Article 42-2(1)(7) relief is unavailable.
The correction interest rate is 31 per 1,000 a year under Enforcement Rule Article 9-3, applied through Decree Article 32-4(4) and Article 56(2).
The late-payment penalty is 22 per 100,000 a day under Decree Article 39(1).
Separate interest or penalties on an import VAT shortfall are not included, so confirm them with your broker.
How to use the calculator
- Enter the importer’s VAT status and the customs value in KRW on a CIF basis.
- Enter the HS codes (optional) and applied rates for the two or three candidates your broker named, and choose the candidate you would declare if importing before the ruling.
- Enter the review type, the planned UNI-PASS filing date, whether analysis is needed and how many items, the expected analysis and correction days, and the broker fee.
- Enter the planned import date, the follow-up days after the notice, the daily waiting cost, and the assumed time to a Customs reassessment for the no-ruling path.
- Review the candidate tax table, the path comparison, the schedule and deadlines, the re-review card and the items to check, then save the review for your broker meeting.
Use the candidate note to record the broker’s order of preference or the heading relied on; it also appears in the saved review.
HS codes are for display only, and the calculator does not judge which classification is correct.
Illustrative example: wait vs early import vs no ruling
Assume goods with a customs value of KRW 50,000,000 whose candidates are A at 0% (the one you would declare) and B at 8%, and a general VAT taxpayer filing a standard request on 2026-11-02 (Monday).
One item needs analysis taking 14 days, the broker fee is KRW 300,000, the planned import date is 2026-11-20 (Friday), follow-up takes 3 days, waiting costs KRW 100,000 a day and the reassessment assumption is 365 days.
Candidate taxes and schedule in the example| Item | Value |
|---|
| Candidate A duty / VAT / total | KRW 0 / 5,000,000 / 5,000,000 |
| Candidate B duty / VAT / total | KRW 4,000,000 / 5,400,000 / 9,400,000 |
| Spread of the tax range | KRW 4,400,000 |
| Clock start / expected notice (standard) / expedited | 2026-11-16 / 2026-12-28 / 2026-12-04 |
| Import-ready date / wait / waiting cost | 2026-12-31 / 41 days / KRW 4,100,000 |
| Ruling cash cost (analysis, broker, VAT) | KRW 360,000 |
Cash to prepare and economic cost by path in the example| Path | Cash to prepare, A to B | Economic cost, A to B |
|---|
| Import after the ruling | KRW 9,460,000 ~ 13,860,000 | KRW 4,430,000 ~ 8,430,000 |
| Apply, then import before the ruling | KRW 5,360,000 ~ 9,768,150 | KRW 330,000 ~ 4,338,150 |
| Declare without a ruling | KRW 5,000,000 ~ 10,106,240 | KRW 0 ~ 4,706,240 |
If B is ruled after an early import, 24 days of correction interest, from the day after the 2026-12-07 due date to the 2026-12-31 correction, add KRW 8,150.
If you declare without a ruling and Customs reassesses to B a year later, a KRW 400,000 under-declaration penalty and KRW 306,240 of late-payment penalty for 348 days are added.
A re-review would have a filing deadline of 2027-01-27 and an expected notice of 2027-03-30, stretching the wait to 133 days.
Reading the result and what to do next
When the tax range is wide
It is safer to set aside cash equal to the spread until the ruling arrives.
Recalculate the selling price and margin on the highest-rate candidate as well, and ask your broker to summarize the basis for each candidate, such as the General Interpretative Rules, heading terms and Explanatory Notes.
When the wait is long
Check whether an expedited review reason applies and whether preparing the sample and composition sheet in advance can shorten correction and analysis time.
If the first shipment cannot be delayed, discuss the rejection risk and the possible extra payment of an early import with the classification office and your broker first.
When documents are missing
Follow the checklist in the calculator to prepare a sample, or three photos or drawings if impractical, the process flow chart, use and product descriptions and Korean translations.
Submit a non-disclosure request for trade secrets, and keep model numbers and photos showing that the goods at clearance are identical.
Frequently asked questions
Who can request an HS advance ruling in Korea, and when?
Customs Act Article 86(1) allows a person who intends to import or export the goods, the manufacturer of goods for export, and a licensed customs broker, broker corporation or clearance agent to apply.
The request must be made before the import or export declaration.
If the same goods have already been declared, Enforcement Decree Article 106(3)(2) allows the application to be rejected, so schedule the request before the first shipment.
Is the 30-day processing period 30 calendar days?
No.
Article 14(4) of the Korea Customs Service notice applies the Civil Petitions Act, and Article 19(2) of that Act counts periods of six days or more in days, including the first day and excluding Saturdays and public holidays.
Thirty days therefore means roughly six weeks, and the 60-day re-review close to three months.
Correction, analysis and committee time are excluded from the period, so the notice moves later by that amount.
Can anyone get expedited review?
The proviso to Article 14(1) of the notice sets a 15-day period where, for example, a declaration is imminent because of shipment or a delay would cause a severe economic loss.
The expedited review request (Form 1-2) must be submitted with the application and the reason must be accepted.
The calculator cannot guarantee acceptance, so also check the standard 30-day schedule.
How much is the analysis fee and when is it paid?
Enforcement Rule Article 33 sets an analysis fee of KRW 30,000 per item for goods that require physical or chemical analysis of their materials.
Under Article 13 of the notice it is paid to the treasury bank before analysis begins and is not refunded once analysis has been carried out, even if the application is later rejected.
An unpaid fee can lead to rejection.
Can I import before the ruling arrives?
You can, but there are risks.
Declaring the same goods during the review can lead to rejection of the application, and you must pay the difference if the ruling carries a higher rate than you declared.
Within six months of declaration and payment you pay the difference by correction with 3.1% annual interest; after that you file an amended declaration with a late-payment penalty.
Check with the classification office and your broker before importing early.
If the ruling gives a lower rate, do I get the tax back?
Under Customs Act Article 38-3(2) you can file a refund claim within five years of the first tax declaration if the declared tax was excessive, and Customs must respond within two months.
The calculator shows the expected refund only and conservatively leaves out refund interest.
Until the refund arrives, that amount stays tied up, so reflect it in the budget.
How long does a ruling stay valid?
Customs Act Article 86(7) keeps a ruling valid until the classification is changed under Article 87.
When the same goods are declared, Customs must apply the notified classification.
If the ruling was based on false information or other fault of the applicant and is later changed, the change can apply retroactively, so describe the goods accurately.
What if I disagree with the ruling?
Under Customs Act Article 86(3) and Article 3 of the notice you can request one re-review within 30 days of receiving the notice.
A re-review takes 60 days counted in business days, and time spent at the Customs Classification Committee is excluded.
Use the re-review card in the calculator to see the extra waiting days and cost before deciding.
Scope and cautions
- The calculator does not classify goods or estimate which candidate is likely to be correct.
It never suggests declaring the lower-rate candidate, and a false declaration can attract a 60% penalty and prosecution.
- The expected notice date is an estimate based on the processing-period rules, not a confirmed clearance date.
Longer correction, analysis or committee review delays it.
- Other internal taxes such as individual consumption tax, FTA origin determinations, quota and anti-dumping duties, interest or penalties on an import VAT shortfall, refund interest and justified-reason relief are not calculated.
- Dates after 2027-12-31 skip weekends only because holiday data is unavailable, and the result flags them for checking.
- Amounts and dates you enter are calculated in your browser only and are not sent to or stored on a server.
Check the official sources and schedule the ruling
Official texts were checked on 2026-10-24.
The Customs Act MST290673 (effective 2026-10-02), its Enforcement Decree MST283621, its Enforcement Rule MST288525 (effective 2026-07-31), the Korea Customs Service notice on classification review and operation (effective 2026-01-02), Civil Petitions Act Article 19 and the public-holiday regulation were confirmed through the Korean Ministry of Government Legislation OPEN API.
Fees, interest rates and processing periods must be rechecked whenever the law or notice changes.
Start by checking the candidate tax range and the cash for each path in the calculator above.
Then prepare the documents on the checklist and agree the filing date and any expedited-review reason with your broker to settle the shipment and the cash plan together.
Build the advance ruling budget review