Special benefits and contribution shares: adjusting inheritance shares and the 2023 ten-year rule

In short: special benefits and contribution shares are mechanisms that adjust each heir's actual share (the specific inheritance share) in situations where applying the statutory shares as-is would be unfair. A special benefit (Article 903 of the Civil Code) works to reduce the share of an heir who received a lifetime gift or a bequest, while a contribution share (Article 904-2 of the Civil Code) works to increase the share of an heir who made a special contribution to maintaining or increasing the deceased's property. However, under Article 904-3 of the Civil Code, effective 1 April 2023, in principle once ten years have passed from the start of the inheritance these claims can no longer be made, and division proceeds on the statutory shares. This article is general information organising the basics of special benefits and contribution shares, the exemption from bringing gifts into account, the ten-year rule, and who to hand valuation, tax and disputes to. Whether something applies in an individual case and the finalisation of amounts are handled by a tax accountant or a lawyer depending on whether there is a dispute.

How do special benefits and contribution shares move the inheritance share?

The statutory shares are the proportions set by the Civil Code according to the combination of heirs. But if only one heir received a large lifetime gift, or conversely supported the deceased's property through the family business or nursing care, dividing strictly by the statutory shares creates unfairness. Special benefits and contribution shares adjust this, and the final share reflecting both is called the specific inheritance share.

System	Basis	Effect	Who is covered
Special benefit	Civil Code, Article 903	Reduces the share of an heir who received a lifetime gift or bequest	Co-heirs
Contribution share	Civil Code, Article 904-2	Increases the share of an heir who made a special contribution to maintaining or increasing the property	Co-heirs

Both are, as a rule, first decided by the co-heirs' division agreement. When agreement cannot be reached, the family court judges them in the division mediation or adjudication. Special benefits and contribution shares are adjustments among "co-heirs"; a contribution by a relative who is not an heir is handled by the separate scheme of the special contribution fee (Article 1050 of the Civil Code), discussed below.

How far does a lifetime gift count as a special benefit? (and the exemption)

A special benefit is at issue where a person received a bequest from the deceased, or a gift for marriage or adoption, or as capital for livelihood (Article 903, paragraph 1 of the Civil Code). Each person's share is calculated on the basis of the property at the start of the inheritance plus the value of the lifetime gift (the deemed inherited property), and a person who received a special benefit takes the remainder after deducting it.

Point	Content
Likely to count	Housing-purchase funds, funds to start a business, large tuition, a marriage/adoption dowry and other gifts as "capital for livelihood"
Unlikely to count	Small assistance, living expenses within the scope of support
Exemption	If the deceased expressed an intention "not to include the special benefit in the calculation of shares," that intention is followed (Article 903, paragraph 3)
Residential property to a spouse	Where a couple married for 20 years or more makes a bequest or gift of the residential building or its site, an exemption is presumed (Article 903, paragraph 4)

The intention to exempt may be express or implied, but to avoid later disputes it can be made clear in a will and the like. Whether something is a special benefit and how much it is valued at is judged case by case, and views among the parties often differ.

Are nursing care or supporting the family business recognised as a contribution share?

A contribution share is recognised where a co-heir made a "special contribution" to maintaining or increasing the deceased's property through methods such as providing labour for the deceased's business, financial contributions, or nursing care for the deceased (Article 904-2, paragraph 1 of the Civil Code). The point is that it must be a "special" contribution — cooperation beyond the level normally expected among relatives.

Item	Content
Typical examples	Supported the family business almost without pay, repaid the deceased's debt with private funds, or quit a job to provide long-term nursing care
Hard to recognise	Cooperation within the scope of ordinary cohabitation or support
How decided	First the co-heirs' agreement. If not reached, the family court decides considering the time, method and degree of the contribution, the amount of the inherited property and all other circumstances (Article 904-2, paragraph 2)
Ceiling	Cannot exceed the property value at the start of the inheritance minus the value of bequests (Article 904-2, paragraph 3)

Where a relative who is not an heir (for example a child's spouse) contributed through nursing care and the like, it may be the object not of a contribution share but of the special contribution fee (Article 1050 of the Civil Code) available for inheritances beginning on or after 1 July 2019. Both contribution shares and the special contribution fee are areas prone to disputes over the amount.

What changed with the "ten years from the start of the inheritance" rule effective in 2023?

Article 904-3 of the Civil Code, newly established in the 2021 reform (effective 1 April 2023), placed a time limit on claims for special benefits and contribution shares. In principle, in a division carried out after ten years have passed from the start of the inheritance, the provisions on special benefits (Article 903) and contribution shares (Article 904-2) do not apply, and division proceeds on the statutory shares.

However, division on the specific inheritance shares remains possible even after ten years in either of the following cases.

• Where an heir requested division of the estate from the family court before ten years passed from the start of the inheritance (Article 904-3, item 1)
• Where, within the six months before the ten-year period expires, an heir who could not request division for compelling reasons requests it from the family court within six months of the reason ceasing (Article 904-3, item 2)

Item	Content
Effective date	1 April 2023
Principle	After ten years from the start of the inheritance, division on the statutory shares
Transitional measure	Where the inheritance began before the effective date, there is a grace of five years from the effective date (until 31 March 2028), and the later of that and the ten-year mark is the reference

This rule does not mean that "division itself becomes impossible after ten years." Division can still be done, but the adjustment reflecting special benefits and contribution shares can, in principle, no longer be made — that is the key point. Where there is an inheritance left unaddressed, it is important to check the starting point of the period early. The whole picture of deadlines is organised in Summary of inheritance deadlines.

Who should handle valuation, tax and disputes? (the scope of the administrative scrivener's role)

Special benefits and contribution shares have situations decided by the parties' agreement and situations that become disputes and go to the family court. The roles divide as follows.

• Preparing the division agreement where agreement has been reached, collecting family registers and organising the inheritance relationships, and gathering the necessary documents → Yotsuba Administrative Scrivener Office (administrative scrivener)
• Where there is a dispute among the parties over whether special benefits or contribution shares apply or over their valuation and a representative is needed, representation in mediation and adjudication → a lawyer
• Valuation of lifetime gifts and real estate, and calculation and filing of inheritance tax and gift tax → a tax accountant
• Registration of inheritance (change of name of real estate) → a judicial scrivener

Yotsuba Administrative Scrivener Office, on the premise that the heirs have reached agreement on how to divide, handles putting that content into documents such as a division agreement. It cannot finalise the amounts of special benefits or contribution shares, nor represent parties in dispute. Where there is a dispute we connect you to a lawyer, and for tax judgements to a tax accountant. Each field is on the premise that you contract separately with each qualified professional as an independent business, and our office receives no referral fee. For the flow of engagement, see Engagement Flow; for fees, see Fee Schedule; for the whole picture of inheritance work, see Inheritance Support; for the basics of statutory shares, see Statutory heirs and shares; for how to make the agreement, see Can I make the division agreement myself?; for the minimum share, see What is the legally reserved portion?; and when things cannot be settled, see The flow of division mediation and adjudication. For the sale or use of inherited real estate, also see Inherited real estate desk by Yotsuba Real Estate Co., Ltd., a separate business.

FAQ

Q. What is the difference between a special benefit and the legally reserved portion?
A. A special benefit (Article 903 of the Civil Code) adjusts each heir's actual share (the specific inheritance share) within the estate division. The legally reserved portion, by contrast, is a minimum share guaranteed by law to heirs other than siblings, a separate scheme to demand payment of money when it is infringed. The two differ in purpose and in deadline. For details of the reserved portion, see What is the legally reserved portion?.

Q. I cared for my parent. Do I always get a contribution share?
A. A contribution share (Article 904-2 of the Civil Code) may be recognised for a "special contribution" beyond ordinary cooperation among relatives that contributed to maintaining or increasing the deceased's property. It is not automatically added just because nursing care took place; the degree of the contribution and whether it was unpaid are considered. Disputes over the amount are common, and if not settled the family court decides.

Q. More than ten years have passed since the inheritance. Can adjustment no longer be made?
A. Under Article 904-3 of the Civil Code, in principle once ten years have passed from the start of the inheritance, special benefits and contribution shares can no longer be claimed. There are exceptions, such as where you had requested division from the family court before the ten years passed, and a transitional measure until 31 March 2028 for inheritances that began before the effective date. The starting point differs by case, so we recommend checking early.

Q. Can I ask an administrative scrivener to calculate special benefits and contribution shares?
A. Where the parties have reached agreement on how to divide, putting that content into documents such as a division agreement is administrative-scrivener work. On the other hand, we cannot represent parties in a dispute over valuation, nor calculate inheritance tax or gift tax. Disputes go to a lawyer, tax to a tax accountant, and registration to a judicial scrivener, each contracted separately as an independent business, to whom we connect you.

Sources (Primary Information)

• e-Gov Law Search, "Civil Code" (Act No. 89 of 1896), Article 903 (special benefits, exemption from bringing gifts into account, and the presumption for a spouse's residential property), Article 904 (loss and the like by the donee's act), Article 904-2 (contribution shares), Article 904-3 (the ten-year time limit from the start of the inheritance), and Article 1050 (the special contribution) (accessed 2026-08-30)
• Ministry of Justice, "On the Act Partially Amending the Civil Code and Others (Act No. 24 of 2021) (mandatory application for inheritance registration, time limit on estate division, etc.)" (the new Article 904-3 of the Civil Code, effective 1 April 2023, and the transitional measure) (accessed 2026-08-30)
• Courts of Japan, "Estate division mediation" and "Mediation to determine a contribution share" (family court procedures) (accessed 2026-08-30)

This article is general information and does not guarantee whether special benefits or contribution shares apply, their valuation, or the outcome of the division. Valuation of amounts, tax judgements, and representation in disputed cases are handled by a tax accountant, a lawyer and a judicial scrivener, each as an independent business under a separate contract. Our office prepares documents on the premise that the heirs have reached agreement, and receives no referral fee. Individual judgements are made by a qualified professional after a meeting. Written by Joji Uramatsu, administrative scrivener and licensed real estate broker.