What is reserved share? Who is entitled?

What the Law Says

Japanese civil law guarantees certain heirs a 'reserved share' — a legally protected minimum portion of the deceased’s estate that cannot be overridden by a will. This ensures basic financial protection for close family members.

The reserved share applies to statutory heirs who are spouses, children (including adopted and acknowledged illegitimate children), and direct ascendants (e.g., parents). Siblings are not entitled to a reserved share.

The size of the reserved share depends on who survives the deceased. If only the spouse survives, their reserved share is one-third of the estate. If only children survive, each child’s reserved share is one-half. If both spouse and children survive, the spouse gets one-third and the children collectively get one-half — divided equally among them. If only parents survive (and no spouse or children), each parent’s reserved share is one-third.

An heir must claim their reserved share within two years from when they learn of the inheritance and the infringement (e.g., a will that reduces their share below the reserved amount).

Statutory Text

A person who has a right to a reserved share may claim reduction of the legacy or gift to the extent necessary to secure the reserved share.

— Civil Code, Art. 1031 — Reduction of Legacy or Gift to Secure Reserved Share

Statutory Text

The reserved share of a spouse is one-third of the value of the property subject to succession; that of a child or direct ascendant is one-half of that value.

— Civil Code, Art. 1028 — Amount of Reserved Share

Statutory Text

The right to claim reduction of a legacy or gift to secure a reserved share shall be extinguished by prescription after two years from the time the heir becomes aware of the commencement of the succession and the making of the legacy or gift.

— Civil Code, Art. 1042 — Period of Prescription

What to Do

Sources