Korean Inheritance Tax Amended Claim After Auction or Expropriation Calculator
Check whether inherited property expropriated, auctioned or publicly sold below its reported value within one year qualifies for the Korean Article 79 special amended claim, find the six-month deadline with Civil Act period rules and holidays, and estimate the 2026 refund with deductions reapplied, installment offset and 3.1% refund interest.
South Korea 2026 · Inheritance and Gift Tax Act Article 79(1)2 · Decree Article 81(3)1 · Framework Act Articles 5 and 52
Initial values are a fictional example. Replace them with the amounts on your return and the price on the distribution table or compensation agreement. The tax office decides the claim and the event date; the calculator uses the dates you enter.
Special claim refund and deadline
Estimated refund (tax reduction)
108,640,000 KRW
Earliest claim deadline
2027-03-18 · 140 days left
Cash refund + interest
109,747,235 KRW
Refund lost to passed deadlines
0 KRW
| Asset | Disposal | Original value | Price | Drop | Event date | Deadline | Days left | Status |
|---|---|---|---|---|---|---|---|---|
| Shop A | Court auction (Civil Execution Act) | 900,000,000 KRW | 620,000,000 KRW | 280,000,000 KRW | 2026-09-18 | 2027-03-18 | 140 days left | Claimable |
| Land B(spouse) | Expropriation (compensation) | 400,000,000 KRW | 340,000,000 KRW | 60,000,000 KRW | 2026-10-05 | 2027-04-05 | 158 days left | Claimable |
| Apartment C | Public sale | 500,000,000 KRW | 530,000,000 KRW | 0 KRW | 2026-10-20 | 2027-04-20 | 173 days left | No drop |
| Case | Gross estate | Taxable value | Spouse deduction | Deductions | Tax base | Computed tax | Filing credit | Final tax |
|---|---|---|---|---|---|---|---|---|
| Before (original return) | 2,800,000,000 KRW | 2,590,000,000 KRW | 700,000,000 KRW | 1,260,000,000 KRW | 1,330,000,000 KRW | 372,000,000 KRW | 11,160,000 KRW | 360,840,000 KRW |
| After (drop applied) | 2,460,000,000 KRW | 2,250,000,000 KRW | 640,000,000 KRW | 1,200,000,000 KRW | 1,050,000,000 KRW | 260,000,000 KRW | 7,800,000 KRW | 252,200,000 KRW |
Refund = original final tax − amended final tax. The drop is not multiplied by a rate; deductions, the deduction limit, progressive rates and the 3% filing credit are reapplied to the reduced estate.
View refund interest, installments and key dates
- Claimable drop
- 340,000,000 KRW
- Installment balance reduced
- 0 KRW
- Cash refund
- 108,640,000 KRW
- Interest days
- 120 days
- Refund interest (3.1% a year)
- 1,107,235 KRW
- Total cash
- 109,747,235 KRW
- One year after the inheritance
- 2027-02-10
- Inheritance tax filing deadline
- 2026-08-31
- End of valuation period (six months)
- 2026-08-10
- Drop past the deadline
- 0 KRW
Deadline = the day six months after the day following the event (Civil Act Articles 157 and 160), moved to the next business day (Framework Act Article 5(1)). Interest = cash refund × 3.1% × days from the day after payment to the decision ÷ 365 (Decree Article 43-3(1)1).
The spouse’s inherited asset fell, so the spouse’s actual share and deduction also fell, reducing the refund.
If inherited property was auctioned or expropriated at a lower price, file the special claim within six months
Korean inheritance tax is reported at market value on the inheritance date.
But an inherited shop or plot can be lost to a court auction over debts, or expropriated for a public project, at a price far below the reported value.
The heir has then paid tax on a higher value than the money actually received.
Article 79(1)2 of the Inheritance and Gift Tax Act lets the heir request a correction within six months from the event when, by the day one year after the inheritance, inherited property is expropriated, auctioned or publicly sold and its value falls.
Because the deadline differs completely from the general five-year amended claim, missing it can forfeit refunds of tens or hundreds of millions of won.
This calculator tests each asset, computes the deadline with Civil Act period rules and the holiday rule, recalculates the refund with all deductions reapplied, and shows the installment offset and national tax refund interest.
Default values are a fictional example, not a real case or a tax office decision.
General amended claim vs the inheritance tax special claim
Both recover overpaid tax, but the basis, grounds and deadlines differ.
A later price drop on disposal is not an error in the original valuation but a change afterwards, so it has its own rule.
| Item | General amended claim | Inheritance tax special claim |
|---|---|---|
| Legal basis | Framework Act on National Taxes Article 45-2(1) | Inheritance and Gift Tax Act Article 79(1)2 |
| Deadline | Within five years after the statutory filing deadline | Within six months from the day the event occurs |
| Ground | The reported tax base or tax exceeded the correct amount (errors, missed deductions) | The value fell through expropriation, court auction or public sale by the day one year after the inheritance |
| Drop test | Not applicable (an error in the return itself) | Compensation, auction or public-sale price < taxable value of that asset (Decree Article 81(3)1) |
| Documents | Claim form and proof of the error | Tax base and tax before and after, plus proof of the ground (Decree Article 81(1)) |
The general five-year claim for income, capital gains or VAT can be estimated with the amended return refund calculator.
Four requirements and the formulas
1. A filer or assessed taxpayer
The heir must have filed the inheritance tax return on time or late, or received an assessment or correction from the tax office (Act Articles 67 and 76).
2. Disposal within one year
The expropriation, Civil Execution Act court auction or public sale must occur by the day one year after the inheritance date, counting from the next day.
3. Price below the taxable value
The compensation, auction or public-sale price must be lower than that asset’s inheritance taxable value as reported or assessed.
4. Claim within six months
The claim form must be filed within six months from the event; a deadline on a holiday moves to the next business day.
Formulas
- Drop per asset = original inheritance tax value − compensation, auction or public-sale price (qualifying assets only)
- Amended gross estate = original gross estate − claimable drops
- Amended spouse share = original spouse share − drops on the spouse’s assets
- Estimated refund = original final tax − amended final tax (recalculated with the same deduction rules)
- Cash refund = estimated refund − min(estimated refund, unpaid installment balance)
- Refund interest = cash refund × 3.1% × (decision date − payment date) ÷ 365
When does the six-month deadline end?
Framework Act Article 4 applies the Civil Act to tax periods.
Under Civil Act Article 157 the event day itself is excluded and counting starts the next day; under Article 160 the period ends the day before the same date six months later, or at month end when that date does not exist.
A period that starts on the 1st ends at the end of the fifth following month.
If the last day is a Saturday, Sunday, public or substitute holiday or Labor Day, Framework Act Article 5(1) moves the deadline to the next day.
| Event date | Six-month end | Claim deadline | Note |
|---|---|---|---|
| 2026-09-18 | 2027-03-18 | 2027-03-18 | Thursday, no move |
| 2026-08-31 | 2027-02-28 | 2027-03-02 | Period starts on the 1st so it ends at February month end; Sunday and March 1 holiday move it to March 2 |
| 2027-02-28 | 2027-08-31 | 2027-08-31 | Period starts March 1, so it ends August 31, not August 28 |
| 2026-10-03 | 2027-04-03 | 2027-04-05 | Saturday, moves to Monday |
The day one year after the inheritance is counted the same way.
For an inheritance on 2026-02-10 only events by 2027-02-10 qualify, and because this is a requirement rather than a filing deadline it does not move on holidays.
How to use the calculator
- Enter the inheritance and reference dates.
The inheritance date gives the one-year limit, the filing deadline and the valuation period; the reference date (today) gives the days left.
Choose whether the original return was on time (3% filing credit) or late or assessed. - Enter the disposed assets.
For each asset enter the disposal type, the original inheritance tax value, the compensation, auction or public-sale price and the event date.
Tick the spouse box when the spouse inherited the asset so the spouse deduction is recalculated. - Enter the estate and deductions from the return.
Enter the gross estate (including disposed assets at original values), debts, funeral costs, the spouse’s actual share, children, net financial assets and gifts within ten years to reproduce the original tax under the 2026 rules.
Enter the actual tax paid to compare with the reproduced amount. - Enter the payment date and installment balance.
The payment date (the last one if paid in parts), unpaid installment balance and expected decision date give the cash refund and refund interest. - Review the result and prepare documents.
Check the estimated refund, the earliest deadline, each asset’s status and the before and after tax table, then save a TXT with the checklist for the claim form and adviser meeting.
Worked fictional example
A decedent died on 2026-02-10 leaving KRW 2.8 billion to a spouse and two children, and the return was filed and paid on time on 2026-08-31.
Debts are KRW 200 million, funeral costs KRW 10 million, the spouse’s actual share KRW 700 million and net financial assets KRW 300 million; the reference date is 2026-10-29.
| Asset | Disposal | Original value (KRW) | Price (KRW) | Event date | Claim deadline | Result |
|---|---|---|---|---|---|---|
| Shop A | Court auction | 900,000,000 | 620,000,000 | 2026-09-18 | 2027-03-18 | Claimable · drop 280,000,000 |
| Land B (spouse) | Expropriation | 400,000,000 | 340,000,000 | 2026-10-05 | 2027-04-05 | Claimable · drop 60,000,000 |
| Apartment C | Public sale | 500,000,000 | 530,000,000 | 2026-10-20 | — | No drop · excluded |
| Item | Before (KRW) | After (KRW) |
|---|---|---|
| Gross estate | 2,800,000,000 | 2,460,000,000 |
| Taxable value (less KRW 200M debts and KRW 10M funeral) | 2,590,000,000 | 2,250,000,000 |
| Spouse deduction | 700,000,000 | 640,000,000 |
| Deductions applied (KRW 500M lump sum, spouse, KRW 60M financial) | 1,260,000,000 | 1,200,000,000 |
| Tax base | 1,330,000,000 | 1,050,000,000 |
| Computed tax | 372,000,000 | 260,000,000 |
| 3% filing credit | 11,160,000 | 7,800,000 |
| Final tax | 360,840,000 | 252,200,000 |
The claimable drop is KRW 280 million on Shop A plus KRW 60 million on Land B, KRW 340 million in total.
The amended final tax is KRW 252,200,000, so the estimated refund is 360,840,000 − 252,200,000 = KRW 108,640,000.
Land B went to the spouse, so the spouse’s actual share falls from KRW 700 million to KRW 640 million and the spouse deduction falls by KRW 60 million.
Had a child received Land B, the amended tax would be KRW 229,890,000 and the refund KRW 130,950,000.
Refund interest for 120 days from the 2026-08-31 payment to an assumed 2026-12-29 decision is KRW 1,107,235, for a total cash refund of KRW 109,747,235.
The earliest deadline is Shop A’s 2027-03-18, so both assets should be claimed together before that date.
Why the refund is not drop × tax rate
Progressive brackets
Inheritance tax rates run in five steps from 10% up to KRW 100 million to 50% above KRW 3 billion.
When the tax base falls across brackets, the same rate does not apply to the whole drop.
In the example the base falls from KRW 1.33 billion to KRW 1.05 billion within the 40% bracket.
Spouse deduction recalculated
The spouse deduction follows what the spouse actually received (at least KRW 500 million, capped by the statutory share and KRW 3 billion).
When the spouse’s asset falls, the deduction falls too and the refund shrinks.
Deduction limit
Inheritance deductions apply only within the limit of the taxable value less added gifts and similar items (Act Article 24).
A smaller estate can make that limit bind.
Filing credit and installments
For an on-time return the 3% filing credit is recalculated on the amended tax.
With an installment balance the reduction lowers the remaining installments first, shrinking the cash refund.
When to use it
A shop auctioned over debts
If the decedent’s loan default led to a voluntary auction of the inherited shop, check the auction price and date on the distribution table and sale approval, then compute the refund and deadline.
Land expropriated for a public project
If a road or housing project expropriated inherited land below the reported value, use the amounts and dates in the compensation agreement or ruling to test the rule.
Property sold in a tax-arrears public sale
If a public sale for unpaid taxes sold inherited property cheaply, track the deadline from the sale decision and payment date.
A sibling preparing for an adviser
Save each asset’s status and the before and after tax table as a TXT to fill in the before and after tax base and tax on the claim form quickly.
Check before you file
- Disposals after one year, or ordinary sales at a low price, do not qualify.
- Event-date interpretations can differ, so track the earliest date and, if documents are late, ask the tax office about filing first and supplementing later.
- Prices within the six-month valuation period can themselves be market value, and some auctions, such as re-acquisition of in-kind tax property by the heirs, are excluded from market value (Decree Article 49(1)3).
- If the fallen asset carried the cohabiting-house, family-business or farming deduction, those deductions may change and need professional review.
- The tax office decides whether to accept the claim; this result is an estimate.
Assumptions
The tax is calculated for a resident decedent with no substitution, bequest or renunciation and with children, under the 2026 deduction rules (KRW 500 million lump sum, spouse deduction of at least KRW 500 million capped by the statutory share and KRW 3 billion, financial asset deduction and the deduction limit).
Appraisal fee deductions, penalties and the cohabiting-house, family-business and farming deductions are not modelled.
Refund interest uses a single last payment date and approximates the reverse ordering of split payments.
The holiday table covers 2025 to 2027; later deadlines only skip weekends.
Frequently asked questions
An inherited apartment sold cheaply at a court auction. Can I get inheritance tax back?
If the Civil Execution Act auction took place by the day one year after the inheritance and the auction price is below the value on the inheritance tax return, Article 79 of the Inheritance and Gift Tax Act allows an amended claim.
You must file within six months from the auction event, and the tax office refunds the difference if it accepts the claim.
An auction after one year or an ordinary sale at a low price does not qualify.
How is this different from the general five-year amended claim?
A general amended claim covers a return that overstated tax, filed within five years after the statutory deadline.
A later drop through expropriation, auction or public sale means the original valuation was correct when made, so a separate special rule applies with a much shorter six-month deadline.
Waiting because five years seem available can cost you the special claim.
When exactly is the event date?
The law only says the day the ground occurs, so for auctions it may be read as the sale approval date or the full payment date, and for expropriation as the agreement or ruling date or the compensation receipt date.
The calculator uses the date you enter, so tracking the deadline from the earliest date is safer.
Confirm the exact start date with the tax office or an adviser.
Is the refund just the drop times the tax rate?
No.
The inheritance tax must be recalculated on the reduced estate.
Progressive brackets shift, the spouse deduction shrinks when the spouse’s asset fell, and the deduction limit and the 3% filing credit are recalculated.
In the fictional example the KRW 340 million drop times the 40% top rate would be KRW 136 million, but the estimated refund is KRW 108,640,000.
What if I am paying in installments?
If an installment balance is still unpaid, the reduction first lowers the remaining installments and only the amount already paid above the amended tax is refunded in cash.
The calculator splits the balance reduction from the cash refund.
Confirm the revised schedule with the tax office.
Do I also receive refund interest?
Framework Act Article 52 adds national tax refund interest.
For a refund from correcting a return, Decree Article 43-3(1)1 runs it from the day after payment to the refund decision at 3.1% a year under Rule Article 19-3.
The calculator applies it only to the cash refund and assumes a decision two months after the reference date by default.
What if the auction ended within six months of the inheritance?
Expropriation, auction or public-sale prices within the six-month valuation period around the inheritance date can themselves be market value (Decree Article 49(1)3).
If the price was known before the filing deadline, the return would normally use it.
If you already filed a higher value, review with an adviser whether this rule or a general claim fits.
Does this cover forced-heirship returns or inheritance recovery suits?
Those fall under item 1 of the same Article 79(1): a final judgment in an inheritance recovery or forced-heirship suit that changes values among heirs.
They are outside this calculator, as are bulk sales of premium-valued shares, sales of mandatorily held shares and the three-month gift tax claims.
Legal sources and reference date
Current texts were verified through the National Law Information OPEN API on 2026-10-29 (Inheritance and Gift Tax Act MST 276123, Decree MST 290845, Framework Act on National Taxes MST 289999, its Decree MST 283623 and Rule MST 284607).
No Supreme Court decision on the Article 79(1)2 requirements was found in the precedent search, so no case is cited.
- Inheritance and Gift Tax Act, Article 79 (special amended claims)
- Enforcement Decree, Article 81 (grounds and claim form)
- Enforcement Decree, Article 49 (valuation principles)
- Inheritance and Gift Tax Act, Article 71 (installment payment)
- Framework Act on National Taxes, Articles 4 and 5 (periods and deadlines)
- Framework Act, Article 52 and Decree Article 43-3 (refund interest)
- Framework Act Rule, Article 19-3 (3.1% a year)
Check your refund deadline now
With each disposed asset’s original value, price and date you can estimate the refund and claim deadline at once.
For the full inheritance tax or a general amended claim, use the calculators below as well.
Related calculators
- Amended Return Refund Calculator (5-Year Retroactive)Estimate a Korean amended-return (claim for correction) refund: the over-paid national tax principal plus statutory refund interest (3.1% per year in 2026) and the 5-year filing window by tax type. Based on the Framework Act on National Taxes Article 45-2 (claim within 5 years after the statutory due date), Article 52 with Enforcement Decree Article 43-3 (interest accrues from the day after payment), and Enforcement Rule Article 19-3 (annual 3.1% rate).
- Inheritance Real Estate Valuation Method CalculatorCompare reporting inherited Korean real estate at the official published price (supplementary method) versus an appraised market value under Inheritance and Gift Tax Act Articles 60-61 and Enforcement Decree Article 49. Weighs the added inheritance tax against the future capital gains tax saved (Income Tax Act) plus the appraisal fee, and flags the NTS appraisal program and the six-month valuation period.
- Gift and Inheritance Tax CalculatorEstimate Korea-related gift or inheritance exposure under simplified tax and asset-growth assumptions.
- Korea Mortgage Auction Withdrawal & Stay Payoff CalculatorEstimate one mortgage auction applicant’s payoff preparation and cash gap, then check withdrawal consent, Article 266 documents and competing auction orders under Korean rules.
- Korea Real Estate Auction Distribution Priority & Recovery CalculatorEstimate creditor-by-creditor recovery from Korean real estate auction proceeds using confirmed ranks, distribution-demand status, same-rank pro rata allocation, and three disputed-right scenarios.
- Korea Expropriation Replacement Acquisition Tax Exemption CalculatorReview replacement-acquisition deadlines, regional and exclusion conditions, eligible compensation and excess acquisition-tax principal under Korean 2026 rules.