厚生年金と国民年金 — 老後の備えと現役の負担

Japan's public pension system has a two-tier structure. The first tier is the "National Pension (Basic Pension)" in which all residents aged 20-59 enroll. The second tier is "Employees' Pension," which company employees and civil servants enroll in additionally. Tier 1 provides a common minimum guarantee for all, while Tier 2 provides additional benefits proportional to remuneration during the active working years.

The National Pension is mandatory for everyone aged 20-59. Insured persons are classified into 3 categories. (1) Category 1 insured person: self-employed, students, unemployed, etc. The individual pays a fixed monthly premium (16,980 yen monthly in fiscal year 2025). (2) Category 2 insured person: company employees and civil servants enrolled in Employees' Pension. No additional burden because the National Pension portion is included in the Employees' Pension premium. (3) Category 3 insured person: a spouse financially supported by a Category 2 person (annual income under 1.3M yen). No premium burden on the individual; the Employees' Pension scheme of which the spouse is a member collectively bears the cost.

Employees' Pension Insurance, like employees' health insurance (shaho), enrolls regular employees working 30+ hours weekly and part-time workers meeting certain conditions. The premium is calculated by multiplying the "standard monthly remuneration" (monthly salary divided into grade brackets) by the premium rate of 18.3% (fixed since September 2017), split 50/50 between employer and employee. The actual individual burden is 9.15%. Premiums are also collected from bonuses at the same rate based on the "standard bonus amount."

Receiving the old-age pension requires a "qualifying period" of in principle 10+ years (120 months), combining premium-paid periods and exemption periods (this was 25 years until August 2017, then amended). In principle, payouts start at age 65, with options for early claim at 60-64 (reduced) or deferred claim at 66-75 (increased).

The old-age basic pension (National Pension portion) pays approximately 830,000 yen annually (about 69,000 yen monthly) in fiscal 2025 when premiums have been fully paid for 40 years (480 months). The Employees' Pension portion (Tier 2) is calculated based on enrollment period and average standard monthly remuneration. The model pension for a typical company employee couple (with a full-time housewife) is approximately 230,000 yen monthly (Employees' Pension + Basic Pension for two people).

When unable to pay premiums, you can apply for exemption at the municipal office. Exemption types include full exemption, 3/4 exemption, half exemption, and 1/4 exemption, determined based on the individual's income. Students have the "Student Payment Exception" (catch-up payment is possible after graduation), and people in their 20s in non-regular employment have the "Payment Deferment System."

Exempted or deferred premiums can be paid catch-up within 10 years. Additionally, those aged 60-64 can use "voluntary enrollment" in National Pension to increase pension amounts, useful when 40 years of full payment have not been reached. Leaving premiums unpaid not only reduces the receivable amount but may also forfeit eligibility for disability pension and bereaved family pension, so caution is required.

Foreigners departing Japan can claim a "lump-sum withdrawal payment" if they meet certain requirements: (1) do not hold Japanese nationality, (2) have 6+ months of National Pension or Employees' Pension premium payment, (3) do not satisfy the old-age pension eligibility period (10 years), (4) are not receiving disability pension etc., (5) do not have a Japan residence, (6) claim within 2 years of last losing eligibility. The payment covers up to a maximum of 5 years (60 months), with 20.42% withholding (including special reconstruction income tax) at the time of payment.

For international workers, "social security agreements" resolve the issues of double pension premium burden and aggregation of enrollment periods. As of 2026, Japan has concluded agreements with over 20 countries including the USA, Germany, South Korea, UK, France, Canada, Australia, and China. When temporarily dispatched between agreement countries (in principle within 5 years), the worker enrolls only in the home country's system and is exempted from the destination country's system.

Aggregation of enrollment periods is a mechanism that sums periods enrolled in both countries' pension systems to determine whether each country's pension eligibility period is satisfied. For example, a person who was enrolled for 5 years in the USA and 6 years in Japan does not satisfy Japan's 10-year requirement alone, but may be able to obtain eligibility through aggregation under the agreement. However, the receivable amount is calculated according to actual enrollment period in each country.