Special Benefit Advancement Calculator | Simulate Each Heir's Concrete Share
Enter the total estate value and each heir's lifetime gifts or bequests (special benefits), and this free simulator automatically calculates the deemed estate, statutory share, and concrete share under Article 903 of Japan's Civil Code.
When some heirs received lifetime gifts or bequests from the deceased, Japan's Civil Code requires "advancing" (adding back) that amount to the estate to work out a fair division — producing a "deemed estate" from which each heir's concrete share is calculated (Article 903). Just enter the total estate value and each heir's relationship and special benefit amount, and this tool automatically estimates the deemed estate, statutory share, and concrete share for every heir. This is a separate topic from the "reserved portion" (forced heirship) — it applies when working out a fair split during the estate division itself.
Simulate from the estate value, heir composition, and special benefits
Tips
- A "special benefit" typically means a gift for marriage or adoption, a gift as capital for a livelihood (such as funds for a home purchase or starting a business), or a bequest. Ordinary allowances or support within the scope of maintenance usually don't count.
- A gift or bequest of residential real estate to a spouse is presumed exempt from advancement if the marriage lasted 20 years or more, so enter 0 for the special benefit amount in that case.
- An ascendant (parent, etc.) doesn't inherit if even one child is alive or has a substitute heir. Adding an ascendant row in that situation is automatically excluded from the calculation.
- When an "excess beneficiary" arises (an heir whose special benefit exceeds their nominal share), the common view is that they simply receive no further estate — they generally aren't required to return the excess.
- The deemed estate and concrete share calculated here are a different concept from the value reported for inheritance tax purposes (the tax valuation before the estate is divided).
Frequently Asked Questions
Side Note — Why does the "advancement" rule exist at all?
The special benefit advancement rule grew out of a simple concern: if one heir already received a large lifetime gift or bequest, and the remaining estate is then split equally while ignoring that fact, the result ends up unfair. For example, if only the eldest son received a large gift to start a business, and the rest of the estate is then divided equally among the siblings without accounting for that gift, the eldest son effectively ends up with more than his fair share.
The calculation works by first adding the special benefit back into the estate to create a "deemed estate," then working out each heir's nominal share according to the statutory shares. Heirs who already received a special benefit then subtract that amount, receiving only the remainder through the estate division. This keeps everyone's final total share fair, regardless of when a gift was actually made.
Japan's 2018 inheritance law reform added a new presumption, aimed at better protecting a long-married spouse's living arrangements: a gift or bequest of residential real estate between spouses married 20 years or more is, in principle, no longer subject to advancement. This is meant to let a surviving spouse continue living in the family home with peace of mind.
The special benefit system also plays a practical role in estate division talks by making visible who received what and when. In discussions that can easily turn emotional, having a concrete calculation as a starting point helps move the conversation forward.