Asked about Japanese National Health Insurance (NHI) or National Pension for self-employed individuals.
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General reference only
This Guide is general tax/accounting reference material for AI-assisted workflows. It has not been reviewed for your personal facts, documents, elections, deadlines, residency, filing status, or local procedures. Do not rely on it to file, pay, amend, or take a tax position without review by a qualified professional in the relevant jurisdiction.
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National Pension monthly premium (FY 2025)
JPY 17,510National Pension Act, Art. 87
National Pension annual total premium (FY 2025)
JPY 210,120National Pension Act, Art. 87
National Pension premium tax deductibility
Fully deductible as social insurance premium deduction; no capNational Pension Act; Income Tax Act (Japan)
NHI Medical component annual cap (FY 2025)
JPY 650,000National Health Insurance Act; Local Tax Act
NHI Support component annual cap (FY 2025)
JPY 240,000National Health Insurance Act; Local Tax Act
NHI Long-term care component annual cap (FY 2025)
JPY 170,000Long-Term Care Insurance Act; National Health Insurance Act
NHI total maximum annual premium (FY 2025)
JPY 1,060,000National Health Insurance Act; Local Tax Act
NHI income-based rate range (varies by municipality)
5–12%National Health Insurance Act; Local Tax Act
NHI per-capita sub-element typical range
JPY 20,000–60,000/yearNational Health Insurance Act; Local Tax Act
NHI per-household sub-element typical range
JPY 0–30,000/year (some municipalities omit)National Health Insurance Act; Local Tax Act
NHI base deduction from prior-year income for income-based calculation
JPY 430,000National Health Insurance Act; Local Tax Act
NHI 70% reduction household income threshold formula
JPY 430,000 + (JPY 100,000 x earners beyond 1)National Health Insurance Act; Local Tax Act
NHI 50% reduction household income threshold formula
JPY 430,000 + JPY 295,000 x insured + (JPY 100,000 x earners beyond 1)National Health Insurance Act; Local Tax Act
NHI 20% reduction household income threshold formula
JPY 430,000 + JPY 545,000 x insured + (JPY 100,000 x earners beyond 1)National Health Insurance Act; Local Tax Act
NHI low-income reduction — portions to which it applies
Per-capita and per-household portions only; NOT income-based portionNational Health Insurance Act; Local Tax Act
National Pension full exemption income threshold (single, approx)
Prior-year income <= JPY 670,000 → JPY 0 premiumNational Pension Act, Art. 90
National Pension 3/4 exemption income threshold (single, approx)
Income <= ~JPY 930,000 → pay 1/4 of standard premiumNational Pension Act, Art. 90
National Pension 1/2 exemption income threshold (single, approx)
Income <= ~JPY 1,410,000 → pay 1/2 of standard premiumNational Pension Act, Art. 90
National Pension 1/4 exemption income threshold (single, approx)
Income <= ~JPY 1,890,000 → pay 3/4 of standard premiumNational Pension Act, Art. 90
National Pension payment deferral (under 50) income threshold (single, approx)
Income <= JPY 670,000 → payment deferredNational Pension Act, Art. 90
National Pension 6-month advance payment discount
~1%National Pension Act
National Pension 1-year advance payment discount
~2%National Pension Act
National Pension 2-year advance payment discount
~4%National Pension Act
National Pension premium monthly due date
End of the following monthNational Pension Act
National Pension payment period
Monthly, April to MarchNational Pension Act
NHI premium payment period (instalments)
Typically June to March (10 instalments)National Health Insurance Act
NHI premium due date
End of each month (varies by municipality)National Health Insurance Act
National Pension Category 1 insured age range
Ages 20–59National Pension Act, Art. 87
NHI Long-term care component age band
Ages 40–64 onlyLong-Term Care Insurance Act; National Health Insurance Act
Tokyo 23 Wards NHI Medical component income rate (illustrative)
~7.17%National Health Insurance Act (Tokyo 23 Wards municipal schedule)
Tokyo 23 Wards NHI Medical component per-capita (illustrative)
~JPY 42,100National Health Insurance Act (Tokyo 23 Wards municipal schedule)
Tokyo 23 Wards NHI Support component income rate (illustrative)
~2.42%National Health Insurance Act (Tokyo 23 Wards municipal schedule)
Tokyo 23 Wards NHI Support component per-capita (illustrative)
~JPY 14,400National Health Insurance Act (Tokyo 23 Wards municipal schedule)
Tokyo 23 Wards NHI Long-term care component income rate (illustrative)
~2.14%Long-Term Care Insurance Act; National Health Insurance Act (Tokyo 23 Wards municipal schedule)
Tokyo 23 Wards NHI Long-term care component per-capita (illustrative)
~JPY 15,600Long-Term Care Insurance Act; National Health Insurance Act (Tokyo 23 Wards municipal schedule)
NHI number of instalments (typical)
10 (June to March)National Health Insurance Act
Quick reference table
| Field | Value |
|---|---|
| Country | Japan |
| Jurisdiction Code | JP |
| Primary Legislation | National Health Insurance Act; National Pension Act |
| Supporting Legislation | Long-Term Care Insurance Act; Local Tax Act |
| Tax Authority | Municipal governments (NHI); Japan Pension Service (National Pension) |
| Tax Year | FY 2025 (April 2025 -- March 2026) |
| Currency | JPY only |
| Contributor | Open Accountants Community |
| Validated By | Pending -- requires sign-off by a Japanese tax accountant or social insurance labour consultant |
| Validation Date | Pending |
| Skill Version | 2.0 |
| Confidence Coverage | Tier 1: National Pension fixed amount, NHI component structure, payment schedules, caps. Tier 2: NHI municipal rate variations, reduction eligibility, partial-year calculations. Tier 3: disability pension, survivors pension, voluntary additional pension. |
National Pension (FY 2025)
| Item | Amount |
|---|---|
| Monthly premium | JPY 17,510 |
| Annual total | JPY 210,120 |
| Category 1 insured | Self-employed, freelancers, students, unemployed aged 20-59 |
| Tax treatment | Fully deductible as social insurance premium deduction |
NHI component structure
| Component | Purpose | Applies To |
|---|---|---|
| Medical | Basic health insurance | All NHI enrollees |
| Support | Elderly health system support | All NHI enrollees |
| Long-term care | Long-term care insurance | Ages 40-64 only |
NHI annual caps (FY 2025)
| Component | Annual Cap |
|---|---|
| Medical | JPY 650,000 |
| Support | JPY 240,000 |
| Long-term care | JPY 170,000 |
| Total maximum | JPY 1,060,000 |
NHI sub-elements per component
| Sub-Element | Basis | Typical Range |
|---|---|---|
| Income-based | Prior-year income minus JPY 430,000 base deduction | 5-12% (varies by municipality) |
| Per-capita | Fixed amount per enrolled person | JPY 20,000-60,000/year |
| Per-household | Fixed amount per household | JPY 0-30,000/year (some omit) |
| Asset-based | Fixed-asset tax | Being phased out |
Low-income reductions (NHI per-capita/per-household only)
| Reduction | Household Income Threshold (2025) |
|---|---|
| 70% reduction | JPY 430,000 + (JPY 100,000 x earners beyond 1) |
| 50% reduction | JPY 430,000 + JPY 295,000 x insured + (JPY 100,000 x earners beyond 1) |
| 20% reduction | JPY 430,000 + JPY 545,000 x insured + (JPY 100,000 x earners beyond 1) |
Conservative defaults
| Ambiguity | Default |
|---|---|
| Unknown municipality | Flag for reviewer -- cannot compute NHI without municipal rates |
| Unknown prior-year income | Use JPY 0 (minimum NHI, possible pension exemption) |
| Unknown age | Assume under 40 (no long-term care component) |
| Unknown shakai hoken status | Assume NOT enrolled (NHI applies) |
Read this whole section before computing anything.
This is the deterministic pre-classifier for bank statement entries related to social insurance. Match by case-insensitive substring.
National Pension debits pattern table
| Pattern | Treatment | Notes |
|---|---|---|
| NENKIN, PENSION, 年金, 国民年金 | NATIONAL PENSION PAYMENT | Monthly premium -- due by end of following month |
| JAPAN PENSION SERVICE, 日本年金機構 | NATIONAL PENSION PAYMENT | Same |
| 年金前納, ADVANCE PENSION | ADVANCE PENSION PAYMENT | 6-month, 1-year, or 2-year advance payment (discounted) |
NHI premium debits pattern table
| Pattern | Treatment | Notes |
|---|---|---|
| NHI, 国民健康保険, 国保, KOKUMIN KENKO | NHI PREMIUM PAYMENT | Municipal billing -- typically June to March (10 instalments) |
| 市区町村, CITY OFFICE, WARD OFFICE | POSSIBLE NHI PAYMENT | Verify -- municipalities bill NHI directly |
| 口座振替 (bank debit) + municipal name | NHI AUTO-DEBIT | Auto-debit for NHI premium |
Long-term care pattern table
| Pattern | Treatment | Notes |
|---|---|---|
| 介護保険, LONG-TERM CARE | LTCI COMPONENT | Included in NHI billing for ages 40-64; separate billing for 65+ |
Employer health insurance pattern table
| Pattern | Treatment | Notes |
|---|---|---|
| 健康保険, KENPO, 協会けんぽ | EMPLOYER HEALTH INSURANCE | Client is on shakai hoken -- STOP, NHI skill does not apply |
| 厚生年金, KOSEI NENKIN | EMPLOYEES PENSION | Client is on shakai hoken -- STOP |
Payment methods and discounts
| Method | Discount |
|---|---|
| Monthly | None |
| 6-month advance | ~1% |
| 1-year advance | ~2% |
| 2-year advance | ~4% |
| Bank transfer (early debit) | Slight additional discount |
Exemptions and deferrals table (National Pension Act, Art. 90)
| Exemption Type | Income Threshold (single, approx) | Payment |
|---|---|---|
| Full exemption | Prior-year income <= JPY 670,000 | JPY 0 |
| 3/4 exemption | Income <= ~JPY 930,000 | 1/4 of standard |
| 1/2 exemption | Income <= ~JPY 1,410,000 | 1/2 of standard |
| 1/4 exemption | Income <= ~JPY 1,890,000 | 3/4 of standard |
| Payment deferral (under 50) | Income <= JPY 670,000 | Deferred |
Because rates vary by municipality, this is a template. Actual rates must be obtained from the client's municipal office.
NHI computation steps
| Step | Action |
|---|---|
| 5.1 | Obtain prior calendar year total income |
| 5.2 | Subtract base deduction: JPY 430,000 to get NHI taxable income |
| 5.3 | For each component (Medical, Support, Long-term care): multiply by municipal income-based rate |
| 5.4 | Add per-capita amount x number of NHI-enrolled household members |
| 5.5 | Add per-household flat amount (if municipality charges it) |
| 5.6 | Cap each component at statutory maximum |
| 5.7 | Sum all three components = annual NHI premium |
| 5.8 | Divide by number of instalments (typically 10) |
Illustrative rates Tokyo 23 Wards
| Component | Income Rate | Per-Capita | Per-Household |
|---|---|---|---|
| Medical | ~7.17% | ~JPY 42,100 | JPY 0 |
| Support | ~2.42% | ~JPY 14,400 | JPY 0 |
| Long-term care | ~2.14% | ~JPY 15,600 | JPY 0 |
These rates are illustrative. Always verify with the specific municipality.
NHI payment schedule
| Detail | Value |
|---|---|
| Payment period | Typically June to March (10 instalments) |
| Due date | End of each month (varies by municipality) |
| Methods | Bank transfer, convenience store, credit card, bank debit |
National Pension payment schedule
| Detail | Value |
|---|---|
| Payment period | Monthly, April to March |
| Due date | End of the following month |
| Methods | Bank transfer, convenience store, credit card, Pay-easy, bank debit |
Situation: Client registers as resident in September. Resolution: NHI prorated from month of registration. Pension owed from month of gaining Category 1 status. Prior-year income may be zero, resulting in low NHI and possible pension exemption. Flag for reviewer.
Situation: Client works part-time (under shakai hoken threshold) and freelances. Resolution: If part-time does not provide shakai hoken, client remains on NHI. Both employment and self-employment income included in NHI calculation. Pension remains Category 1.
Situation: Client turns 40 in October. Resolution: Long-term care component starts from the month the client turns 40. NHI premium recalculated mid-year.
Situation: Client turns 60 in March. Resolution: Category 1 obligation ends the month before turning 60. May optionally continue as voluntary insured. Escalate for advice on voluntary continuation.
Situation: Freelancer earns JPY 10,000,000. Resolution: Income-based portion will be high, but each component is capped. Total NHI cannot exceed JPY 1,060,000.
Situation: Client has not paid NHI for 12 months. Resolution: Municipality may issue short-validity insurance card or qualification certificate requiring 100% upfront payment. Pension non-payment reduces future benefits and may affect disability pension eligibility.
When a Tier 2 situation is identified:
REVIEWER FLAG
Tier: T2
Client: [name]
Situation: [description]
Issue: [what is ambiguous]
Options: [possible treatments]
Recommended: [most likely correct treatment and why]
Action Required: Qualified professional must confirm before advising client.
When a Tier 3 situation is identified:
ESCALATION REQUIRED
Tier: T3
Client: [name]
Situation: [description]
Issue: [outside skill scope]
Action Required: Do not advise. Refer to qualified professional. Document gap.
Input: Age 35, single, prior-year income JPY 5,000,000, no other household NHI members. Expected output: NHI taxable income = 5,000,000 - 430,000 = JPY 4,570,000. Medical: ~JPY 369,769. Support: ~JPY 124,994. Long-term care: N/A (under 40). Total NHI: ~JPY 494,763. Pension: JPY 210,120. Total: ~JPY 704,883.
Input: Age 28, single, prior-year income JPY 300,000. Expected output: NHI taxable income = JPY 0. Income-based = JPY 0. 70% reduction on per-capita. Medical per-capita: JPY 12,630. Support: JPY 4,320. Total NHI: ~JPY 16,950. Pension: full exemption likely.
Input: Age 45, single, prior-year income JPY 20,000,000. Expected output: Medical capped at JPY 650,000. Support capped at JPY 240,000. Long-term care capped at JPY 170,000. Total NHI: JPY 1,060,000. Pension: JPY 210,120. Total: JPY 1,270,120.
Input: Age 30, registers residency in July (9 months). Expected output: NHI prorated x 9/12. Pension: JPY 17,510 x 9 = JPY 157,590.
This skill and its outputs are provided for informational and computational purposes only and do not constitute tax, legal, or financial advice. Open Accountants and its contributors accept no liability for any errors, omissions, or outcomes arising from the use of this skill. All outputs must be reviewed and signed off by a qualified professional (such as a tax accountant, social insurance labour consultant, or equivalent licensed practitioner in Japan) before filing or acting upon.
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Other Japan computations in the OpenAccountants Tax Library.
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