# Deduction Catalog

Purpose: Read this when checking deduction eligibility, blue filing benefits, tax credits, or overlap-sensitive items such as Furusato Nozei and under-16 dependents.

## Contents

- [Income deductions](#income-deductions)
- [Tax credits](#tax-credits)
- [Blue filing special deduction](#blue-filing-special-deduction)
- [Priority checks](#priority-checks)
- [Overlap-sensitive cases](#overlap-sensitive-cases)

## Income Deductions

### Personal Deductions

| # | Deduction | Amount | Main requirement |
|---|-----------|--------|------------------|
| 1 | Basic deduction (`基礎控除`) | Up to JPY 480,000 (`R7` note: `580,000`) | Total income `<= JPY 25 million`, phased down above `JPY 24 million` |
| 2 | Spouse deduction (`配偶者控除`) | Up to JPY 380,000 (`480,000` for elderly spouse) | Spouse income `<= JPY 480,000`, taxpayer income `<= JPY 10 million` |
| 3 | Spouse special deduction (`配偶者特別控除`) | Up to JPY 380,000 | Spouse income between `JPY 480,001` and `JPY 1.33 million` |
| 4 | Dependent deduction (`扶養控除`) | JPY 380,000 to JPY 630,000 | Relative income `<= JPY 480,000` |
| 5 | Disability deduction (`障害者控除`) | JPY 270,000, `400,000`, or `750,000` | Qualifying disability status |
| 6 | Widow deduction (`寡婦控除`) | JPY 270,000 | Taxpayer income `<= JPY 5 million` |
| 7 | Single-parent deduction (`ひとり親控除`) | JPY 350,000 | Taxpayer income `<= JPY 5 million` |
| 8 | Working-student deduction (`勤労学生控除`) | JPY 270,000 | Working student with income `<= JPY 750,000` |

### Dependent-Deduction Bands

| Category | Age | Amount |
|----------|-----|--------|
| General dependent | 16 or older | JPY 380,000 |
| Specific dependent | 19 to under 23 | JPY 630,000 |
| Elderly dependent living together | 70 or older | JPY 580,000 |
| Elderly dependent living separately | 70 or older | JPY 480,000 |

> Children under 16 do not qualify for income-tax dependent deduction, but they still affect resident-tax non-taxable thresholds. Keep the `住民税に関する事項` entry in scope.

### Other Income Deductions

| # | Deduction | Amount | Main requirement |
|---|-----------|--------|------------------|
| 9 | Social-insurance deduction (`社会保険料控除`) | Full amount | National pension, health insurance, long-term care insurance, and similar payments |
| 10 | Small-business mutual aid deduction (`小規模企業共済等掛金控除`) | Full amount | iDeCo, `小規模企業共済`, corporate DC, and similar contributions |
| 11 | Life-insurance deduction (`生命保険料控除`) | Up to JPY 120,000 | General / medical-care / personal-annuity categories |
| 12 | Earthquake-insurance deduction (`地震保険料控除`) | Up to JPY 50,000 | Qualifying earthquake-insurance premiums |
| 13 | Medical-expense deduction (`医療費控除`) | Up to JPY 2 million | `(medical cost - insurance reimbursement) - lower of JPY 100,000 or 5% of income` |
| 14 | Donation deduction (`寄附金控除`) | Donation minus JPY 2,000 | Furusato Nozei, certified NPOs, and similar donations; capped at 40% of income |
| 15 | Casualty loss deduction (`雑損控除`) | Loss minus 10% of income | Disaster, theft, or embezzlement loss |

### Employment-Income Adjustment Deduction

Apply when salary income exceeds JPY 8.5 million and one of the listed conditions is met (`租税特別措置法第41条の3の3`).

| Condition | Amount |
|-----------|--------|
| Taxpayer is a specially disabled person | `(salary income - JPY 8.5 million) x 10%`, capped at JPY 150,000 |
| Has a dependent relative under 23 | Same |
| Has a spouse or dependent who is specially disabled | Same |

> This is an adjustment to employment income, not an income deduction. In e-Tax it is often calculated automatically from the withholding slip and dependent data.

### Self-Medication Tax System

- Eligible spending: designated OTC medication purchases
- Amount: purchase cost minus JPY 12,000, capped at JPY 88,000
- Requirement: the taxpayer took a health check, vaccination, or similar preventive measure
- Use either this system or the standard medical-expense deduction, not both

### iDeCo Contribution Limits

| Subscriber type | Monthly limit | Annual limit |
|-----------------|---------------|--------------|
| Self-employed (`第1号`) | JPY 68,000 | JPY 816,000 |
| Company employee without corporate pension | JPY 23,000 | JPY 276,000 |
| Company employee with only corporate DC | JPY 20,000 | JPY 240,000 |
| Company employee with DB or similar plan | JPY 12,000 | JPY 144,000 |
| Public servant | JPY 12,000 | JPY 144,000 |
| Homemaker (`第3号`) | JPY 23,000 | JPY 276,000 |

## Tax Credits

| Credit | Amount | Main requirement |
|--------|--------|------------------|
| Housing-loan credit (`住宅借入金等特別控除`) | Year-end balance x 0.7% | Home purchase / renovation meeting statutory requirements |
| Dividend credit (`配当控除`) | Dividend income x 10% or 5% | Only when comprehensive taxation is chosen |
| Foreign tax credit (`外国税額控除`) | Foreign income tax paid | Double-tax relief |
| Political-donation credit | `(donation - JPY 2,000) x 30%` | Qualifying political donations |
| Certified-NPO donation credit | `(donation - JPY 2,000) x 40%` | Choose either tax credit or income deduction |
| Disaster relief credit | Full to one-quarter reduction | Disaster damage to home or property |

### Housing-Loan Credit Overview (`令和4年` move-in or later)

| Housing type | Debt cap | Credit rate | Period |
|--------------|----------|-------------|--------|
| Certified new home | JPY 45 million | 0.7% | 13 years |
| ZEH-level energy-efficient home | JPY 35 million | 0.7% | 13 years |
| Energy-standard home | JPY 30 million | 0.7% | 13 years |
| Other new homes | JPY 0 from `令和6年` onward | — | — |
| Certified used home | JPY 30 million | 0.7% | 10 years |
| Other used home | JPY 20 million | 0.7% | 10 years |

## Blue Filing Special Deduction

| Amount | Requirement |
|--------|-------------|
| JPY 650,000 | Double-entry bookkeeping plus e-Tax filing or compliant electronic bookkeeping |
| JPY 550,000 | Double-entry bookkeeping without the e-Tax / electronic-bookkeeping condition |
| JPY 100,000 | Simple bookkeeping or non-business-scale real-estate income |

### Main Benefits

1. Special deduction up to JPY 650,000
2. Full expense treatment for `青色事業専従者給与` with prior filing
3. Net-loss carryforward for three years
4. Net-loss carryback for refund claims
5. Immediate expensing of assets under JPY 300,000, up to JPY 3 million per year
6. Bad-debt reserve rules for eligible receivables

### Blue Filing Deadlines

| Case | Deadline |
|------|----------|
| New business started between January 1 and January 15 | March 15 of that year |
| New business started on or after January 16 | Within two months from the start date |
| White return to blue return switch | March 15 of the year to apply |

## Priority Checks

Use this order when the user asks where to check first for tax savings:

1. `小規模企業共済等掛金控除` (iDeCo and similar)
2. `社会保険料控除`
3. `医療費控除`
4. `寄附金控除` (`ふるさと納税`)
5. Housing-loan tax credit
6. `生命保険料控除`

## Overlap-Sensitive Cases

### Furusato Nozei

Once a final tax return is filed, every one-stop filing becomes invalid.

| Situation | Required handling |
|-----------|-------------------|
| One-stop filing already submitted but the taxpayer now files a return | Enter every municipality again as donation deduction |
| No one-stop filing submitted | Enter every municipality normally |

> Do not leave only part of the one-stop filing in place. Filing a return voids all of it.

### Dependents Under 16

- No income-tax dependent deduction applies.
- The child still matters for resident-tax non-taxable thresholds.
- Keep the child in `住民税に関する事項` to avoid missing that resident-tax treatment.

> Amounts and requirements are year-sensitive. If the active filing year is uncertain or changed by reform, pair this file with the tax-law update disclaimer from `references/disclaimer-templates.md`.
