Overview of the Joint Custody System
On April 1, 2026, Japan's revised Civil Code (Act No. 33 of 2024) took effect, allowing joint custody after divorce for the first time in Japanese legal history. Previously, only sole custody was permitted. The revision introduces an opt-in joint custody system.
How to Choose Between Sole and Joint Custody
Under the revised Article 819 of the Civil Code, custody is determined as follows:
| Method | Details |
|---|---|
| Mutual agreement | Parents choose sole or joint custody by agreement |
| Family court | If no agreement is reached, the court decides based on the child's best interests |
The family court evaluates factors including parental cooperation, involvement with the child, and living conditions.
Mandatory Sole Custody for DV and Abuse Cases
Revised Article 819(7) requires sole custody when:
- A parent poses a risk of physical or psychological harm to the child (abuse)
- One parent is at risk of committing domestic violence against the other
This exclusion is mandatory — joint custody cannot be imposed in DV or abuse situations.
New Statutory Child Support
The revision establishes statutory child support (Article 766-3). Even without a separate agreement, a custodial parent can claim ¥20,000 per month per child as a legally guaranteed minimum. Key features include:
- Automatic application when no support agreement exists
- Statutory lien priority over other general claims
- Additional claims for higher amounts remain possible
Impact on Already-Divorced Parents
Under the transitional provisions, parents who divorced before the enforcement date may apply to the family court to change to joint custody. Court approval is based on the child's best interests.
Practical Considerations
- Under joint custody, both parents must agree on major decisions (education, medical treatment)
- Day-to-day care decisions can be made by the custodial parent alone
- In urgent situations, either parent can exercise parental authority unilaterally
- Creating a parenting plan is strongly recommended when choosing joint custody
