Japan's Ministry of Justice Civil Affairs Bureau has published an outline of the Act Partially Amending the Civil Code and Related Laws (Act No. 45 of 2026), promulgated on June 24, 2026. For the adult guardianship system, the three-tier structure of guardianship (kōken), curatorship (hosa) and assistance (hojo) is reorganized: guardianship and curatorship are abolished and unified into the "assistance" system, in which a person is given representative or rescission powers only for the matters actually needed. The system takes effect on a date to be set by Cabinet Order within 2 years and 6 months of promulgation (counting from the promulgation date, no later than December 2028). As of the end of December 2025, there were 180,828 guardianship users, 58,162 curatorship users and 18,078 assistance users.
Background and Legislative History
The Ministry cites rising and diversifying needs for the adult guardianship and will systems due to population aging and more single-person households, a stronger principle of respecting self-determination regardless of disability, the growing importance of wills in addressing the problem of land with unknown owners, and the need for the will system to respond to digital technology. Deliberation began in February 2024 when the Minister of Justice consulted the Legislative Council; the Council compiled an outline and reported to the Minister in February 2026; the Cabinet approved the bill in April 2026; the House of Councillors passed it in June 2026; and it was promulgated on June 24, 2026.
The Problem Under Current Law: "Guardianship" Over-Restricts Self-Determination
Under current law, the available system is fixed by the degree of the person's capacity to appreciate their own affairs: assistance for "insufficient" capacity, curatorship for "markedly insufficient" capacity, and guardianship when capacity is "habitually lacking." Once a person is found to habitually lack capacity, only guardianship — in which the guardian holds comprehensive representative and rescission powers — is available, even if the family wants the system for a specific purpose such as dividing an estate, so self-determination is restricted more than necessary. Guardianship and curatorship also cannot be ended unless capacity is recovered, and replacing a guardian was limited to grounds focused on the guardian's side, such as misconduct (e.g., embezzlement) or serious misbehavior.
Main Changes to the Adult Guardianship System
- Unification into assistance: where a person's capacity is insufficient, the person consents, and the system is needed, the court may, for specified acts individually, grant the assistant representative power (e.g., representation in dividing an estate) or rule that the assistant's consent is required (acts done without consent can be rescinded). Guardianship and curatorship are abolished (Civil Code Arts. 7, 9, 11)
- "Specified assistance" mechanism: if a person under assistance is found to habitually lack capacity, they may choose a mechanism making all statutorily listed important property acts rescindable (Civil Code Art. 10). Where it is used, the court hears the opinion of two or more physicians, and a formal medical evaluation is unnecessary when the need is clearly absent (Domestic Relations Case Procedure Act Art. 119)
- Ending use of the system: even without recovery of capacity, the family court may end the system on application or ex officio when it finds the need has ended (Civil Code Art. 12), including when this is found during the assistant's mandatory yearly status report to the court
- Respect for the person's views: "the person's opinion" is placed first among factors to consider when appointing an assistant (Art. 876-2), and the assistant must grasp the person's wishes by appropriate means such as providing information and listening to the person (Art. 876-11)
- New ground for dismissal: an assistant can be dismissed when "especially necessary for the person's interests," even without misconduct such as embezzlement — e.g., when the assistant does not meet the person and so the person cannot receive appropriate protection (Art. 876-5)
- Predictable remuneration: the content of the assistant's work is made an explicit factor in setting remuneration (Art. 876-19), and results of cases where remuneration claims were granted are planned to be published
Post-Death Affairs, Family Court Procedure and Special Agents
Because unification into assistance could leave post-death matters unattended, the assistant's powers are expanded: an assistant may conclude contracts for the cremation and burial of the person's body and take acts necessary to preserve estate property within the scope of authority held at death (Civil Code Art. 876-26). One example given is an assistant who was granted representation for a care-facility admission contract and payment of fees paying unpaid fees after the person's death. Under current law, only guardians have post-death authority.
In family court proceedings, hearing the person's own statement is in principle required even for decisions to commence assistance, to grant representative power, or to require the assistant's consent. The court is also expressly allowed to ask municipal mayors and other suitable persons for opinions on the person's physical and mental condition and living situation, since the need for assistance is judged not only medically but in light of the person's life circumstances (Domestic Relations Case Procedure Act Art. 120). In addition, when the counterparty to a declaration of intent habitually lacks capacity and has no one to receive it, the family court may appoint, at the declarant's request, a special agent to receive the declaration (Civil Code Art. 98-3; Domestic Relations Case Procedure Act Art. 149-2).
Changes to the Voluntary Guardianship System
- When the family court finds clearly no need for a voluntary guardianship supervisor, it may supervise directly without appointing one (Voluntary Guardianship Contract Act Art. 7)
- Voluntary guardianship contracts may continue even after assistance begins; the basic approach is to set the assistant's representative scope to avoid overlap, with a new rule on partial cancellation of the voluntary guardianship contract where adjustment is needed
- The person and the designated voluntary guardian may agree on the order in which contracts take effect — a way to prepare for the death of the first voluntary guardian (Arts. 4, 5)
- A person designated by the principal in a notarial deed may also apply to the court to activate the voluntary guardianship contract, even if not a relative; similar provisions apply to applications to commence assistance (Voluntary Guardianship Contract Act Arts. 5, 6; Civil Code Arts. 7, 8)
Will System Changes in the Same Act
The same Act also revises the will system: it creates the "deposited-certificate will" (hokan shōsho yuigon), in which will data created on a computer or a printout is submitted to the Legal Affairs Bureau and the testator orally states the full text in person or by web conference before the Bureau stores it (Civil Code Art. 968-2; Will Custody Act Arts. 7, 8), and makes the seal optional (Civil Code Arts. 968, 970, 976, 979, 980). The will provisions take effect on a date set by Cabinet Order within 1 year of promulgation (3 years for items requiring system modification). See our article on the abolition of the seal requirement and new digital will.
Transitional Measures: What Happens to Current Users
- Guardianship/curatorship users who wish to continue: generally may continue under the current law's content; however, the new dismissal grounds and the duty to respect the person's wishes follow the amended Civil Code (Suppl. Arts. 2, 3)
- Those wishing to move to the new system: apply under the amended assistance system; the existing guardianship/curatorship commencement ruling is rescinded (Suppl. Arts. 2, 3)
- Those wishing to end use: may apply to rescind the commencement ruling (Suppl. Arts. 2, 3); eligible applicants include the person, spouse, relatives within the fourth degree, and the guardian or curator
- Current assistance users: may continue under the amended assistance system (Suppl. Art. 4); may apply to rescind the ruling to end use
- Voluntary guardianship contracts concluded before the effective date: the amended Act applies, but effects arising under the old law are preserved (Suppl. Art. 6)
According to the Supreme Court General Secretariat Family Bureau's "Overview of Adult Guardianship Cases (January-December 2025)," users as of the end of December 2025 were: guardianship 180,828, curatorship 58,162, and assistance 18,078.
Practical Points
- The effective dates are not yet fixed (adult guardianship: within 2 years 6 months of promulgation; will system: within 1 year, or 3 years for items requiring system changes). Current guardianship and curatorship users are not immediately affected on the effective date and can generally continue under the current content
- Moving to the new system or ending use after the effective date requires an application to the family court (eligible applicants: the person, spouse, relatives within the fourth degree, guardian or curator, etc.)
- For those considering voluntary guardianship, the key changes are that such contracts survive the start of assistance and that the assistant's representative scope is adjusted to avoid overlap
Sources
- Ministry of Justice Civil Affairs Bureau, outline of the Act Partially Amending the Civil Code and Related Laws (Act No. 45 of 2026), promulgated June 24, 2026: https://www.moj.go.jp/content/001465481.pdf
- Supreme Court General Secretariat Family Bureau, "Overview of Adult Guardianship Cases (January-December 2025)" (user numbers as cited in the Ministry's material)