Japan Inheritance Documents — Signature Certificates, Affidavits, and Apostilles

Japan's inheritance system relies on two verification mechanisms that most foreign heirs don't have: the family register (Koseki) and the personal seal (Inkan). If you're a foreign heir living outside Japan, you need legally recognized substitutes for both — and getting them wrong means banks and the Legal Affairs Bureau reject your filing outright.

The Signature Certificate

Japanese heirs sign legal documents — especially the Inheritance Division Agreement (Isan Bunkatsu Kyogisho) — with their registered personal seal and attach a Seal Registration Certificate (Inkan Shomeisho). Foreign heirs without a Japanese seal use a Signature Certificate (Signature Shomeisho) instead.

To obtain one, you sign the document in the physical presence of either:

• A notary public in your country of residence, or
• A consular officer at a Japanese embassy or consulate

The notary or consular officer certifies that the signature is genuine and was made in their presence. This certified signature carries the same legal weight as a Japanese seal impression.

For the Inheritance Division Agreement specifically, you must sign the agreement itself in front of the notary — not sign it at home and then have the signature notarized after the fact. The witnessing of the act of signing is the critical legal requirement.

Notarized Affidavits for Identity and Address

Since foreign heirs can't produce a Japanese Residence Certificate (Juminhyo), they need a Notarized Address Affidavit instead. This is a sworn statement executed before a notary public declaring:

• Your full legal name (matching your passport exactly)
• Your current residential address
• Your relationship to the deceased
• Your nationality and passport number

Some institutions also require a separate Kinship Affidavit — a sworn statement establishing your family relationship to the deceased, supported by certified copies of birth certificates, marriage certificates, or other civil records.

These affidavits must be complete, in a format that Japanese institutions recognize, and accompanied by certified translations into Japanese.

The Hague Apostille

If your country is a party to the Hague Apostille Convention, documents notarized in your country may need an apostille before Japanese institutions accept them. The apostille is a standardized international certification that authenticates the notary's signature and authority.

To get a document apostilled:

1. Have the document notarized by a local notary public
2. Submit the notarized document to your country's designated apostille authority (in the US, this is typically the Secretary of State's office)
3. The apostille is attached to or stamped on the document

For Japanese-issued documents that need to be used abroad, Japan's Ministry of Foreign Affairs (Gaimusho) issues apostilles. Submit the original document to the Gaimusho's Authentication Division in Tokyo or Osaka.

If your country is not a Hague Convention member, the document needs consular legalization instead — a more complex process that involves certification by your country's foreign affairs ministry, then authentication by the Japanese embassy or consulate in your country.

Translation Requirements

Every foreign-language document submitted to a Japanese institution must be accompanied by a complete Japanese translation. The translation must include:

• The translator's full name
• The translator's signature or seal
• A statement certifying the translation is accurate and complete

The translator doesn't need to be officially certified — but incomplete or inaccurate translations will be rejected. Pay particular attention to name spellings, dates (Japanese institutions use both Western and Japanese era calendars), and addresses.

Common Rejection Reasons

Banks and the Legal Affairs Bureau reject foreign documents for:

• Name mismatches between the affidavit, passport, birth certificate, and any Japanese records
• Incomplete translations that summarize rather than translate every field
• Missing apostille when required by the accepting institution
• Affidavit signed outside the notary's presence — the signature must be witnessed
• Expired notarization — some institutions require documents notarized within the past three to six months

The Japan Death Guide for English Speakers includes bilingual affidavit templates and a step-by-step apostille guide for major countries.

See more Japan guides →