Japan Inheritance Division Agreement — How to Prepare It, What to Include, Required Documents, and Common Pitfalls

When there are multiple heirs, how the estate is divided is determined by a discussion among all heirs (遺産分割協議, inheritance division conference). The written record of that agreement is called the "Inheritance Division Agreement" (遺産分割協議書, Isan Bunkatsu Kyogisho). This document is the foundation of virtually every inheritance procedure — real estate title registration, bank account transfers, estate tax filing, and more. This article explains the legal significance of the document, how to prepare it, what documents are needed, and common pitfalls.

What Is an Inheritance Division Agreement?

Steps to Preparing an Inheritance Division Agreement

• ① Identify all heirs
  Collect all family register documents tracing the deceased from birth to death, and confirm who the legal heirs are. Missing an heir causes serious problems later. Using the Statutory Heir Information Certificate system is effective here.
• ② Survey and list all estate assets
  Identify all assets: real estate (property register, fixed asset tax certificate), bank accounts (balance certificates), securities, vehicles, and debts. If assets are discovered after the agreement is signed, a supplemental agreement will be needed.
• ③ Hold the inheritance division conference
  All heirs must agree on who receives what. Physical meetings are not required — agreement can be reached by correspondence, email, or phone — but each heir must sign the document individually.
• ④ Draft the agreement
  Put the agreed terms in writing. Having an administrative scrivener, judicial scrivener, or attorney prepare the draft is generally recommended.
• ⑤ All heirs sign, affix registered seal, and attach seal registration certificates
  Each heir signs the document, affixes their registered seal (実印), and attaches their seal registration certificate (印鑑証明書) obtained from their municipal office.

Key Contents of the Agreement

• Deceased's name, date of death, last registered domicile, and last address
• All heirs' names, addresses, and dates of birth
• Specific identification of each asset (for real estate: location, lot number, land category, area, building number; for bank accounts: bank name, branch, account number, balance)
• Who will receive each asset, stated explicitly
• If there are debts: who bears them and in what proportion
• A "subsequently-discovered assets" clause: how assets found after signing are to be handled
• Date of agreement and signature / registered seal of every heir

Common Issues and Pitfalls

• One heir refuses to sign
  The agreement cannot be completed without unanimous consent. If an heir refuses, a family court mediation or adjudication (調停・審判) petition becomes necessary.
• Insufficient asset description
  "Long-term deposit at Bank A goes to the eldest son" is insufficient if there are multiple accounts. Account numbers must be specified.
• An heir lacks mental capacity (dementia, etc.)
  Signatures from persons lacking capacity are legally void. An application for appointment of a adult guardian (成年後見人) at the family court is required.
• Including a person who renounced inheritance
  Someone who has renounced their inheritance is no longer an heir and must not be included in the agreement.

How Sakura Central Legal Office Can Help

We prepare Inheritance Division Agreements, conduct heir identification research, survey estate assets, and handle all associated transfer procedures — as a complete service through our licensed administrative scriveners. Whether you can't reach one of the heirs, the estate is complex, or you're unsure whether a draft agreement is legally sound, please contact us for a free initial consultation.