Timeline
The 9-Month Korean Inheritance Tax Deadline
In Brief
Overseas heirs have 9 months from the end of the month of death to file Korean inheritance tax (residents: 6 months). Missing it triggers a 20% non-filing penalty plus daily interest at 8.03% annualized.
How the Deadline Is Calculated
Article 67 of the Korean Inheritance and Gift Tax Act requires filing within 6 months from the last day of the month in which the inheritance commenced — extended to 9 months for overseas heirs.
| Heir lives… | Deadline |
|---|---|
| In Korea (resident) | 6 months from end of month of death |
| Overseas (US, etc.) | 9 months from end of month of death |
Example: death on March 15, 2026 → counted from March 31 → overseas heir files by December 31, 2026.
The Same Clock as US Form 706
US Form 706 estate tax is also due in 9 months. The Korean tax should be paid first so you can claim the Form 706-CE foreign death tax credit. Both deadlines run in parallel — start immediately.
Penalties for Missing It
- Failure to file (무신고가산세): 20% of tax due (40% if intentional)
- Failure to pay (납부지연가산세): 0.022% per day (~8.03% annualized)
On a ₩300M tax bill missed by six months, penalties can exceed ₩70M.
Installment Options
- 2-installment (분납): 50% by deadline, 50% within 2 months, no interest
- Long-term (연부연납): up to 10 years for real-estate-heavy estates, with a 3.1% (2026) surcharge and collateral
Can You Get an Extension?
Extensions exist only for narrow cases — undetermined heirs, unvaluable assets, force majeure — and must be applied for before the deadline. "I didn't know" is not accepted. If a Korean parent passed away even a year ago and you haven't filed, file now: voluntary late filing carries lower penalties than enforcement discovery.
General information only, not legal advice. Consult a licensed Korean CPA & Tax Accountant.