The Deduction Stack: Basic, Spouse, Dependent, and Social Insurance
Japan income tax deductions shrink your taxable income before the bracket rates ever touch it. This guide stacks every major deduction in computation order, with amounts dated to current NTA tables, including the revised basic deduction that took effect for 2025 income.12
Procedures, fees, and requirements can change. Confirm current details at the National Tax Agency site. This article is general information, not tax advice; for your specific case, consult a licensed tax accountant (zeirishi).
Overview
Deductions, or 所得控除 (shotoku kojo, "income deductions"), come off your income first; the seven progressive bands price only what remains.2 Two facts make the stack worth learning in order: the basic deduction changed shape in December 2025, so pre-2026 guides quote a flat 480,000 yen that no longer describes most earners; and each deduction has its own channel, with some riding payroll paperwork and others requiring a filed return.12
The stacking order
The computation runs the same way for employees and filers: total income by category, minus the income deductions below, equals taxable income.2 Every deduction subtracts from the same income, so the order among them does not change the total.2 It still helps to meet them in three groups: the universal basic deduction, the family deductions, and the payment-linked deductions.2
The diagram shows deduction groups in presentation order only; every group subtracts from the same income total before the bands apply (as of 2026-09).2
Basic deduction: everyone, now income-linked
The 基礎控除 (kiso kojo, "basic deduction") applies to every resident taxpayer, but since December 1, 2025 it scales with the taxpayer's total income, applying to Reiwa-7 (2025) income onward (as of 2026-09; confirm current figures with the NTA).12
| Taxpayer total income (as of 2026-09) | Basic deduction |
|---|---|
| Up to 1,320,000 yen | 950,000 yen |
| Up to 3,360,000 yen | 880,000 yen |
| Up to 4,890,000 yen | 680,000 yen |
| Up to 6,550,000 yen | 630,000 yen |
| Up to 23,500,000 yen | 580,000 yen |
| 23,500,000 to 24,000,000 yen | 480,000 yen |
| 24,500,000 to 25,000,000 yen | 160,000 yen |
| Above 25,000,000 yen | Zero |
The table as a whole reflects the NTA basic-deduction schedule (as of 2026-09).12 Amounts step down between 24,000,000 and 25,000,000 yen; confirm the exact intermediate row in the current NTA table before filing near those lines.
Pre-2026 guides quote 480,000 yen as the basic deduction for everyone. That figure now applies only to the 23.5 to 24 million yen band (as of 2026-09).2 A typical earner sees 580,000 yen or more, so budgeting with the old number overstates taxable income.
Spouse and dependent deductions
Spouse deduction and special spouse deduction
The 配偶者控除 (haigusha kojo, "spouse deduction") gives a headline 380,000 yen when the spouse's total income is 480,000 yen or less and the taxpayer's own total income is 9,000,000 yen or less, phasing down at higher taxpayer incomes (as of 2026-09; confirm current figures with the NTA).3 Where the spouse earns above the 480,000 yen line, the 配偶者特別控除 (haigusha tokubetsu kojo, "special spouse deduction") offers partial relief up to 380,000 yen through its phase band instead of dropping to zero at once (as of 2026-09).4
Eligibility tests the spouse's income and the taxpayer's income separately. A raise on either side can shrink the relief, so re-check both lines each year rather than assuming last year's deduction repeats.
Dependent deduction by age band
The 扶養控除 (fuyo kojo, "dependent deduction") pays a headline 380,000 yen per qualifying dependent aged 16 or older (as of 2026-09).5 Two age bands pay more: specific dependents (特定扶養親族, ages 19 to 22) give 630,000 yen, and elderly dependents (老人扶養親族, 70 and older) give 480,000 yen, or 580,000 yen for a cohabiting elderly parent or equivalent (as of 2026-09).5 Children under 16 do not generate this deduction; they sit under the child-benefit system instead.5
Social-insurance and small-business-mutual-aid deductions
The 社会保険料控除 (shakai hokenryo kojo, "social-insurance deduction") deducts the full amount of health-insurance, pension, and care premiums paid during the year, with no cap (as of 2026-09).6 For employees the employer-handled share already flows through payroll; premiums paid directly, including arrears or family-member shares paid by the taxpayer, enter through year-end paperwork or a filed return.6
The 小規模企業共済等掛金控除 (shokibo kigyo kyosai-to kakekin kojo, "small-business-mutual-aid deduction") works the same uncapped way and covers iDeCo contributions in full (as of 2026-09).7 Each yen of iDeCo contribution therefore saves national tax at the contributor's marginal slice, which is why the pension guide in this series treats iDeCo as a tax decision as much as a savings one.
Uncapped deductions are worth more per yen to higher-band taxpayers, because each yen escapes the top slice first. That arithmetic favors maxing social-insurance and iDeCo contributions before chasing capped reliefs below.
Life-insurance, earthquake-insurance, and donation deductions
Life-insurance relief (生命保険料控除) is capped: newer-contract categories cap at 40,000 yen each for income tax within an overall ceiling, so large premiums buy only bounded relief (as of 2026-09; confirm current figures with the NTA).8 Earthquake-insurance relief (地震保険料控除) caps at 50,000 yen for income tax (as of 2026-09).9
Donation relief (寄附金控除) deducts qualifying donations minus a 2,000 yen floor, capped at 40 percent of total income (as of 2026-09).10 The furusato nozei program is one application of this deduction, but its caps, gift mechanics, and one-stop filing procedure deserve their own walkthrough, which the companion hometown-tax guide provides.
US persons: Japan deductions stay in Japan
Japan-side deductions reduce Japan taxable income only; nothing on this page transfers onto a US return. Overlap relief between the two systems runs through the foreign tax credit within statutory limits, not through carrying Japanese deductions across the border.11
Treaty positions can also re-characterize income before deductions even apply, which is detail for the treaty siblings rather than this stack. Readers with cross-border facts should put both returns in front of a licensed tax accountant before assuming either computation is final.11
Good to know
The Reiwa-7 basic deduction rewards lower incomes most
Earners with total income under 6,550,000 yen now see 630,000 to 950,000 yen of basic deduction instead of the old flat 480,000 (as of 2026-09).2 Anyone who estimated 2025 tax with a pre-December-2025 guide overstated taxable income, in some cases by nearly half a million yen.
Non-resident dependents need paperwork, not just a name on a form
Resident employees claiming relatives who live abroad must attach the prescribed document set for each non-resident relative. Payroll asks for these before December, so expatriates supporting family overseas should prepare the packet early in the assignment rather than at filing week.
Residence-tax deductions are close but not identical
Basic and several personal deductions carry different amounts on the residence-tax side, so the income-tax stack computed here does not set the June residence-tax bill one to one. The residence-tax interaction guide built alongside this series owns those differences; do not copy income-tax figures onto residence-tax estimates.
Deduction errors still count as filing errors at renewal time
Proper performance of public duties including tax is a stated criterion for permanent residence, and even late-paid amounts count against the applicant in principle (as of 2026-02-24).12 A missed dependent document or a copied-forward spouse claim that no longer qualifies is still an error on a filed return; keep the evidence behind every line claimed.
See also
- Shakai Hoken Overview
- iDeCo: The Private-Pension Path
- Japan Income Tax Brackets and the Reconstruction Surtax
- Furusato Nozei: The Hometown-Tax Hack
- Zeirishi: Tax Accountants in Japan
- Child Benefit (Jidō Teate)