Deductions

Deductions (控除) are the steps that turn your gross pay into the taxable income the brackets actually see. Get the deductions right and the tax follows; get them wrong and every downstream figure is wrong. The 2025 reform (令和7年度税制改正) reshaped several of them for the 2026 (Reiwa 8) income-tax year, and added an entirely new one — so this page is worth reading even if you thought you knew the numbers.

Employment-income deduction (給与所得控除)

This is the first cut, and it applies to salary earners automatically — a standard allowance in place of itemising work expenses. It turns gross salary into “employment income,” and its floor is now ¥650,000 under the reform. That is the figure to use for the 2026 (Reiwa 8) income-tax year; the older, lower pre-reform floor is superseded, and copy that still quotes it is out of date. The statute expresses the low end as a ¥4,000-step lookup table, which this tool approximates with a smooth formula — a few-hundred-yen difference is possible and disclosed.

Basic deduction (基礎控除)

Everyone gets a basic deduction, but the 2025 reform made it income-tested and, for now, non-monotonic: it reaches up to ¥950,000 at lower total incomes and steps down as income rises, disappearing entirely at the very top. The higher middle-tier amounts are temporary figures for the 令和7・8年分 (2025 and 2026) that revert in later years — so this is a deduction whose value genuinely depends on the year as well as your income.

Dependent and spouse deductions (扶養控除・配偶者控除)

If you support qualifying relatives or a spouse, dependent and spouse deductions reduce your taxable income further. Each is keyed to the relative’s age and income and to your own income, with the spouse deduction phasing out as the taxpayer’s income rises. The amounts are below.

What is NOT stated here is the age band that puts a relative in one class rather than another. The amounts above are quoted from our source; the age detail behind the classes (for example the 19–22 and 70+ ones) is paraphrased from general knowledge rather than from a verbatim statutory quote, so it is treated as an unconfirmed estimate and left out rather than stated as fact. Which class a particular relative falls into is the question to take to the source or to a tax professional.

The new specified-relative special deduction (特定親族特別控除)

This is the reform’s headline addition and the fix for the so-called “¥1.03m wall” — the income threshold at which a student or young relative’s part-time earnings used to cost the household a dependent deduction. The new deduction applies to a relative aged roughly 19–22 whose own income sits in a defined band, and it slides — largest at the bottom of the band and tapering to nothing at the top — so a little more earned income no longer triggers a cliff. It is modelled as its own income-tested deduction, separate from the ordinary dependent deduction, effective for 2026.

The calculator defaults to the common case — single, no dependents — and exposes the dependent, spouse and specified-relative inputs for when they apply. No amount here carries the reviewer’s sign-off; the age bands noted above are the honest soft spots and are flagged as such rather than presented as settled.