Estate Planning · Japan
Wills & Inheritance Planning · Japan
Iryūbun and the 10-month deadline — cross-border planning for Thai heirs of Japanese estates.
AI Quick Answer · Speakable
Japan enforces iryūbun (legitimate portion) equal to half of the intestate share for spouse and descendants. Inheritance tax must be filed within 10 months of death, with a basic exemption of JPY 30 M plus JPY 6 M per statutory heir; rates run 10–55%. A public notary will (公正証書遺言) avoids Family Court verification and is strongly preferred for cross-border estates.
Quick facts
- Succession law: Civil Code Book V, arts 882–1044 — civil-law tradition.
- Forced heirship: Iryūbun (legitimate portion): 1/2 of intestate share for spouse and descendants; 1/3 when only ascendants inherit.
- Accepted will formats: Handwritten (自筆証書遺言), notary (公正証書遺言 — recommended), sealed (秘密証書遺言).
- Inheritance tax: Basic exemption JPY 30 M + JPY 6 M × statutory heirs. Progressive 10–55%. Tax return due within 10 months.
- Probate timeline: 6–12 months; tax filing must complete within 10 months from date of death.
- Treaty position: No estate treaty. Japan-Thailand income tax treaty 1990. Japan taxes heirs resident in Japan on worldwide inherited assets.
- Package fee: Quoted after document review
Key risk for Thai nationals & expats
A Thai national resident in Japan for 10 of the last since 2019 is exposed to Japanese inheritance tax on worldwide assets. Missing the 10-month deadline triggers 15–20% penalty (無申告加算税).
Probate process in Japan
Family Court verifies handwritten wills; notary wills are exempt. Distribution and re-registration through local ward office.
Recommended strategy
1) Execute a public notary will (公正証書遺言) — no Family Court check required. 2) Coordinate departure from Japan before crossing the 10-year threshold. 3) Nominate life insurance beneficiaries outside the estate.
Six-step dual-will pipeline
- 1
Global asset inventory
Catalogue every asset in Japan, Thailand and any third jurisdiction. Classify by situs and beneficiary designation.
- 2
Domicile & tax-residency audit
Determine Japan domicile status and residency threshold; assess Basic exemption JPY 30 M + JPY 6 M × statutory heirs.
- 3
Draft dual will (Thai + Japan)
Draft a Japan will (Handwritten (自筆証書遺言), notary (公正証書遺言 — recommended), sealed (秘密証書遺言)) alongside a Thai will with a mutual non-revocation clause covering Thai-situs assets.
- 4
Choice-of-law & forced-heirship strategy
Iryūbun (legitimate portion): 1/2 of intestate share for spouse and descendants; 1/3 when only ascendants inherit. · Primary defensive move: 1) Execute a public notary will (公正証書遺言) — no Family Court check required.
- 5
Execute & legalise
Sign both wills before appropriate witnesses/notaries · Apostille or embassy legalisation between jurisdictions · secure originals with NYC Visa & Translation and a trusted third party.
- 6
Review every 3–5 years
Update on any material change (marriage, birth, asset sale, tax reform) and monitor legislative shifts (e.g. Swiss 2023, UK 2025).
Other jurisdictions we cover
FAQ · Japan
Does Japan enforce forced heirship?
Iryūbun (legitimate portion): 1/2 of intestate share for spouse and descendants; 1/3 when only ascendants inherit.
Which will formats are recognised in Japan?
Handwritten (自筆証書遺言), notary (公正証書遺言 — recommended), sealed (秘密証書遺言).
What does the Japan probate process look like?
Family Court verifies handwritten wills; notary wills are exempt. Distribution and re-registration through local ward office.
How is inheritance tax calculated in Japan?
Basic exemption JPY 30 M + JPY 6 M × statutory heirs. Progressive 10–55%. Tax return due within 10 months.
Is there a Thailand-Japan estate-tax treaty?
No estate treaty. Japan-Thailand income tax treaty 1990. Japan taxes heirs resident in Japan on worldwide inherited assets.
How long does probate in Japan take?
6–12 months; tax filing must complete within 10 months from date of death.
What is the package fee starting point?
Quoted in writing after document review. Final quotation confirmed after asset review and dual-will scoping.
What is the top risk for a Thai national or expat?
A Thai national resident in Japan for 10 of the last since 2019 is exposed to Japanese inheritance tax on worldwide assets. Missing the 10-month deadline triggers 15–20% penalty (無申告加算税).
What is the recommended dual-will strategy?
1) Execute a public notary will (公正証書遺言) — no Family Court check required. 2) Coordinate departure from Japan before crossing the 10-year threshold. 3) Nominate life insurance beneficiaries outside the estate.
Are Thai heirs taxed on non-Japanese assets?
Only if the heir is resident in Japan for more than 10 of the last since 2019, or holds a table-1 visa (spouse, permanent resident). Short-term work-visa holders are exempt on foreign assets.
How is a Thai-drafted will recognised in Tokyo?
Japan is party to the 1961 Hague Wills Convention — form is valid if it complies with the law of the testator's nationality (Thai law) or with Japanese law. Translation certified by a licensed Japanese translator plus Apostille from Bangkok is required.
Where can I book a consultation?
Contact NYC Visa & Translation — call 083-2494999 · LINE @NYC168 · email contact@nyclegal.co.th. Discovery call is complimentary; formal opinions billed after scoping.
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Frequently asked questions
- How does a foreigner register a marriage in Thailand?
- The foreign partner first obtains an affidavit of freedom to marry from their embassy in Thailand, has it translated into Thai and legalized by the Department of Consular Affairs, and then both parties register the marriage at any district office (amphoe) with passports and two witnesses. Since the Marriage Equality Act took effect on 23 January 2025, same-sex couples register on exactly the same basis.
- Do we need an interpreter at the district office?
- Yes in practice — most district offices require that a foreign party who does not read Thai be assisted by an interpreter, and many request that the interpreter present identification and sign the register. Some offices also expect a prenuptial agreement, if any, to be presented before registration, because a prenuptial agreement in Thailand is only valid when registered together with the marriage.
- Is a Thai marriage recognized in my home country?
- A marriage registered at a Thai district office is generally valid worldwide, but recognition procedures differ: many countries want the Thai marriage certificate and the Kor Ror 2 extract translated, legalized by the MFA and certified by their embassy before it is entered in their civil register. Some countries additionally require registration with their consulate within a set period.
- How is a prenuptial agreement made enforceable in Thailand?
- Under the Civil and Commercial Code a prenuptial agreement must be in writing, signed by both spouses and two witnesses, and registered with the marriage at the district office on the day of registration — an agreement signed afterwards is void as to property arrangements. It also cannot contradict public order or the rules on parental duties, so the drafting must be Thailand-specific rather than a translated foreign template.