"If I keep it in cash, the inheritance tax won't be found out." "If I move it into an account in my child's name, I'll be fine." These are the most common misconceptions on the front lines of inheritance. The statistics show the opposite. In on-site inheritance tax examinations, unreported assets are found in about 85% of cases, and the No.1 type of missed asset is cash and deposits. The typical examples are cash hoarded at home (tansu yokin) and deposits held in another's name but effectively owned by the deceased (meigi yokin). This article explains why they get found, at what point they are judged to be "the deceased's property," and how to legally reduce them rather than hide them.
(1) In on-site inheritance tax examinations (8,556 cases in the FY Reiwa 5 administrative year), non-compliance (unreported assets, etc.) was found in 84.2% of cases, and additional tax collected reached a record-high ¥85.7 billion[National Tax Agency].
(2) The largest category of unreported assets is cash and deposits (about 30% of the total), with cash hoarded at home and deposits held in another's name at the center of it.
(3) The tax office accumulates the deceased's lifetime income and asset information via the KSK system, and in an examination it can query financial institutions for roughly the past 10 years of transactions. "The inheritance is far too small relative to lifetime income" is analyzed immediately.
(4) A deposit held in another's name is judged not by "whose name is on it" but by "who provided the original funds and who managed it."
(5) The correct answer is not to hide it, but legitimate countermeasures such as gifts made during one's lifetime (¥1.1 million per year) and the taxation system for settlement at the time of inheritance. If caught, the heavy additional tax of 35% means it becomes a major loss rather than tax saving.
Why it gets found (what the tax office can see)
- Lifetime accumulated data: The KSK system stores information such as the deceased's past tax returns, withholding, real estate, stocks, purchases and sales of gold (payment records), and insurance payouts. If there is a large gap between "assets estimated from lifetime income" and "the inheritance reported," the case is selected for examination.
- Retroactive account queries: Examiners can query financial institutions for past transactions (in practice about 10 years) of the accounts of the deceased and "family members." Large withdrawals just before death (turning it into cash hoarded at home) and regular transfers into family accounts surface here.
- The fate of cash hoarded at home: In addition to the risk of theft or disaster while stored, cash creates a record when it is spent or deposited. In practice, it is not uncommon for other heirs to report it when they clash over the division of the estate.
Criteria for judging a deposit held in another's name (the name does not decide it)
Even for "an account in the name of a child or grandchild," the judgment is made by the following substance. This is the point most frequently flagged in inheritance tax examinations.
| Judgment factor | Likely treated as the deceased's property (deposit held in another's name) | Likely treated as the person's own property |
|---|---|---|
| Original funds | Deposited by the deceased (a high-balance account of a full-time homemaker or child with no income) | The person's own income, or funds with a completed gift contract |
| Management | The deceased keeps the passbook, seal, and cash card | The account holder themselves keeps and uses them |
| Awareness | The account holder does not know the account exists | They are aware they received a gift and can freely use it |
| Records | There is no gift contract and no filing | There is a gift contract and a gift tax filing for years exceeding ¥1.1 million |
In other words, a gift is not established by "intending to have given it." The "secret savings" account of a full-time homemaker is, in principle, judged to be the husband's inheritance property if the original funds come from the husband's income (the attribution of household surplus is a frequent point of dispute in examinations).
The cost when caught (hiding it doesn't pay)
- Unreported assets incur an additional tax for understatement (10–15%), and if intentional concealment is recognized, a heavy additional tax of 35% (40% if unfiled) plus delinquency tax.
- Inheritance tax rates are 10–55%. For example, if concealment of ¥30 million of cash hoarded at home is discovered, the main tax + heavy additional tax + delinquency tax can make roughly half of the hidden amount disappear.
- In the FY Reiwa 5 administrative year, additional tax collected on unfiled cases also hit a record high of ¥12.3 billion. The assumption that "it should be under the basic deduction" often turns out to exceed it once deposits held in another's name are added (calculating the basic deduction).
Correct countermeasures (reduce without hiding)
- Properly establish gifts made during your lifetime: Draw up a gift contract, transfer to an account managed by the recipient, and put it in a state where the recipient can use it freely. Within the annual ¥1.1 million basic deduction, no filing is required (the correct way to use the tax-free allowance. Beware of the add-back for the 7 years before inheritance).
- The ¥1.1 million deduction of the taxation system for settlement at the time of inheritance (from 2024) and as-needed support for education costs (tax-free from the start) are also effective.
- If you already have a deposit held in another's name: The principle is to correctly report it as the deceased's property at the time of inheritance. If you want to sort it out during your lifetime, consult a tax accountant on how to re-conclude the gift contract afresh.
- Keep records of the use and source of cash. Records are what protect your family.
FAQ
Is cash hoarded at home really found out?
It is grasped with high probability. The tax office accumulates the deceased's lifetime income and asset information, and large withdrawals before death come to light through queries to financial institutions (in practice about 10 years). The statistics tell the real story: unreported assets are found in 84.2% of on-site inheritance tax examinations, and the largest category is cash and deposits.
I have transferred money into an account in my child's name every year. Does this count as a gift?
If the parent manages the passbook and seal and the child does not know the account exists or its balance, the gift is not established, and in principle it is judged to be the parent's inheritance property as a "deposit held in another's name." You need to draw up a gift contract and put it in a state where the child themselves can manage and use it.
Is a full-time homemaker's secret savings also subject to inheritance tax?
If the original funds come from the husband's income, in principle it must be included in the husband's inheritance property and reported. Even when saved through many years of household budgeting, in practice it is judged on the basis of the original funds.
What should I do about a deposit already held in another's name?
When inheritance occurs, the principle is to correctly include it as the deceased's property in the filing (hiding it incurs the heavy additional tax of 35%). During your lifetime, there are methods such as re-establishing it as a formal gift or planfully moving it within the ¥1.1 million range; if the amount is large, we recommend consulting a tax accountant.
Sources of the data
- 8,556 on-site examinations; 84.2% non-compliance rate; ¥85.7 billion additional tax (record high); the largest category of unreported assets is cash and deposits; ¥12.3 billion additional tax on unfiled cases: National Tax Agency, Status of Inheritance Tax Examinations, etc. in the FY Reiwa 5 Administrative Year (in Japanese) (PDF)
- Heavy additional tax (35%, 40%): Ministry of Finance, Overview of the additional tax system (in Japanese)
* This article explains the system and introduces legitimate countermeasures; it does not encourage the concealment of assets. For individual judgments, please consult a tax accountant or the tax office.