Korea tax guide
Korea Income Tax Interim Prepayment: November Notices for Foreigners
Income Tax
Who this guide is for
- Foreign resident sole proprietors receiving Korean income tax notices
- Freelancers with business income and changing profits
- Double-entry bookkeeping taxpayers checking obligations without a notice
Quick Answer
Korean income tax interim prepayment (중간예납) is a November advance payment separate from VAT and the annual May return. The ordinary statutory payment date is November 30; the NTS 2026 estimated-reporting guidance also lists November 30, 2026. Check your taxpayer category, notice and any applicable extension before paying or using the first-half estimated-reporting route.
Key points
- Read the tax name: income tax interim prepayment is separate from VAT.
- Check the notice and current deadline instead of assuming every taxpayer is covered.
- A decline in sales alone does not establish estimated-reporting eligibility.
- Save interim payment evidence for annual reconciliation.
Detailed explanation
What the November payment covers
Income Tax Act Article 65 uses January 1 through June 30 as the interim period and generally bases the assessed payment on half the statutory prior-year income tax base. The ordinary collection date is November 30. This is an advance income tax payment, not a separate tax on foreign nationality.
Read the full notice before acting. Confirm your name, taxpayer identifier, tax name, period, amount and payment reference. Keep an electronic copy together with the envelope or delivery record.
Three different tax tasks
| Task | What to check |
|---|---|
| Income tax interim prepayment / 중간예납 | Notice, taxpayer category and first-half reporting rules |
| VAT preliminary notice / 부가가치세 예정고지 | VAT registration and its separate payment instructions |
| Annual global income tax return / 종합소득세 확정신고 | Full-year income, allowable expenses and prepaid tax |
Use the VAT preliminary notice guide if the document is a VAT bill. For annual filing, start with global income tax filing.
Check whether the rules apply to you
The NTS lists exclusions, including specified income-only situations and qualifying new-business cases. Do not assume every foreign worker owes an interim payment merely because they filed an annual return. Conversely, a business owner should not assume employment withholding resolves business-income obligations.
Bring the notice, prior return and business commencement details to the tax office or your representative when your category is unclear. Check actual taxpayer status rather than using the visa label as the answer.
When first-half estimated reporting matters
The NTS 2026 guidance allows estimated reporting when calculated first-half income tax is below 30% of the interim base. That is a tax calculation test, not a sales-decline test. It also describes mandatory reporting for certain resident double-entry bookkeeping taxpayers with first-half business activity but no interim base.
The guidance lists November 30, 2026 as the submission and payment deadline. It explains that a below-threshold calculated payment can still require submission to cancel a notice. Confirm the applicable route before simply paying less.
Prepare January-June books, expense evidence and withholding records. Identify missing transactions and ask your representative to check the calculation before choosing this route. For records, see bookkeeping requirements.
A practical action checklist
- Identify whether the document is income tax, VAT or local tax.
- Match its period and identity details to your records.
- Check the payment date and any extension actually granted to you.
- Review exclusions or estimated reporting before changing the requested payment.
- Use official payment instructions and save the completed transaction receipt.
- Keep any submitted return and acceptance record with the calculation papers.
If you need online payment navigation, see how to pay Korean tax online. Opening a payment page is not proof that the transaction completed.
Keep the annual reconciliation file
Store the interim notice, payment confirmation and any estimated return together. When preparing the annual return, compare these records with the prepaid tax shown in the calculation. Investigate mismatches instead of entering the same amount twice or assuming it was imported.
This guide was reviewed on October 11, 2026. Recheck official November instructions and your own notice before acting, because later relief or individual extensions may affect the payment date. Complex residence, bookkeeping or classification questions need an individual review.
Documents you may need
- Interim income tax notice
- Prior annual return
- January-June books
- Withholding receipts
- Payment records
Common mistakes
- Treating a November prepayment as completion of the annual return
- Confusing the 30% test with a fall in sales
- Ignoring a notice because current profit is lower
- Assuming no notice always means no obligation
- Forgetting prepaid tax when preparing the annual return
When should you ask a tax professional?
Ask a qualified tax professional if you have income from several countries, business income, unclear tax residency, treaty questions, missing documents, late filing concerns, or a visa situation that depends on tax records. This site explains general patterns only and cannot review your personal facts.
FAQ
When is the 2026 income tax interim prepayment deadline?
The ordinary statutory payment date is November 30. The NTS 2026 estimated-reporting guidance specifies November 30, 2026 for that return and payment. Confirm your notice and any individual extension.
Does this replace May income tax filing?
No. Review annual filing separately and reconcile applicable interim payments with the annual calculation.
Can lower sales automatically cancel the notice?
No. The estimated-reporting test concerns calculated first-half income tax relative to the statutory interim base, not simply a percentage decline in sales.
What if I did not receive a notice?
Check whether an exclusion applies and whether your bookkeeping category creates an estimated-reporting obligation. The absence of a letter alone does not answer those questions.
Official Sources to Verify
Check the tax year, eligibility conditions, and publication date in the official material before applying a rule. A link marked “Service portal” helps you find a service; it does not substantiate a particular rate or entitlement.