NZ vs Japan Tax — Side-by-Side Comparison for 2025

Retirement: KiwiSaver vs EPI + iDeCo

Japan's mandatory retirement system is the Employees' Pension Insurance (EPI, 厚生年金保険). The combined contribution rate is 18.3% of standard monthly remuneration (9.15% employee, 9.15% employer), capped at a standard remuneration ceiling of approximately ¥650,000/month. EPI is administered by the Japan Pension Service (日本年金機構) and provides a defined benefit at age 65, scaled to years of contribution and salary.

Above the mandatory EPI floor, Japan offers iDeCo (個人型確定拠出年金) — a voluntary defined-contribution pension. Contributions are fully tax-deductible (reducing both national and resident tax), investment growth is tax-exempt, and withdrawals from age 60 benefit from the generous "retirement income deduction" (退職所得控除). Annual limits: ¥276,000/year for employees who also participate in a corporate defined-benefit pension; up to ¥816,000/year for those without an employer pension. Compared to voluntary KiwiSaver top-ups, iDeCo has a stricter lockup — funds are not accessible before age 60 except in very narrow hardship situations.

Japan also has a generous retirement income deduction (退職所得控除) for lump-sum retirement payments: ¥400,000 × years of service (under 20 years), then ¥700,000 × additional years. Long-tenured employees with 30-year careers can shelter very large retirement payouts from tax — a structural benefit NZ does not offer.

If you're moving NZ → Japan

• Work visas: Common visa categories for NZ citizens include Engineer/Specialist in Humanities/International Services (技術・人文知識・国際業務), Highly Skilled Professional (高度専門職), and Specified Skilled Worker (特定技能). The NZ–Japan EPA does not include a dedicated working holiday scheme at the level of other bilateral agreements, but a Working Holiday visa is available for those under 30.
• Tax residency triggers: You become a Japan tax resident when you establish domicile or reside in Japan for 1+ year. In practice, the 183-day threshold in a calendar year is the critical point to monitor. Japan taxes only Japan-source income (and foreign income remitted) for the first 5 years of cumulative residency in past 10 years.
• 5-year threshold — worldwide income: After 5 cumulative years of residency in the past 10 years, Japan taxes your worldwide income (not just Japan-source). Foreign income earned abroad and not remitted to Japan is still in scope.
• 10-year threshold — worldwide inheritance: After 10 cumulative years of residency in the past 15 years, Japanese inheritance and gift tax applies to your worldwide assets. This is a critical planning threshold — NZ property, KiwiSaver, and investments are all in scope.
• My Number: Register for a My Number (マイナンバー) card at your local ward office within 14 days of establishing residency (jūminhyō registration). Required for payroll, tax filing, and pension enrollment.
• Health insurance: Enroll in employer health insurance (社会保険) via your employer — this happens automatically when you join a company covered by EPI. If self-employed or working for a non-covered employer, join National Health Insurance (国民健康保険) at your local ward office within 14 days of establishing residency.
• KiwiSaver: No trans-Tasman portability scheme exists between NZ and Japan. Your KiwiSaver balance remains in NZ and continues to grow, but you cannot transfer it to a Japanese pension fund. You can still access it at NZ retirement age (65) or via first-home withdrawal if you meet NZ criteria.

If you're moving Japan → NZ

• NZ tax residency: Triggers after 183 days in any 12-month period, or earlier if you establish a permanent place of abode in NZ. Japan residency ends once you deregister from your jūminhyō (住民票) and leave, though the 5-year and 10-year cumulative thresholds continue to count historical years.
• Japan–NZ Double Tax Agreement (DTA): Japan and New Zealand signed a DTA in 1963 (with protocols). The DTA prevents most double taxation of employment income, business profits, dividends, interest, and royalties — allocating taxing rights to the country of residence or source based on article type. Ensure any Japan-source income (rental, pension, business) is correctly reported to IRD under the DTA.
• EPI pension entitlement: Accumulated EPI entitlement is preserved by the Japan Pension Service. You receive EPI retirement benefits at age 65, paid in JPY to a nominated bank account (including overseas accounts). If you leave Japan permanently before completing 10 years of contributions (the minimum for a pension entitlement), you can claim a lump-sum withdrawal payment (脱退一時金) within 2 years of leaving Japan — subject to Japanese withholding tax (20%) but potentially reducible under the DTA.
• KiwiSaver opt-in: There is no automatic enrolment mid-career in NZ — you'll need to actively opt in to KiwiSaver through your NZ employer and choose a contribution rate (3%–10%).
• Lower effective take-home at mid incomes: Moving from Japan to NZ may feel like a tax reduction at first (no resident tax layer, no reconstruction surtax), but the absence of NZ's basic deduction means take-home on the same nominal salary at lower-to-mid incomes can be comparable or even less in NZ once NZD/JPY purchasing power is factored in.