👔 Sole Proprietor Social Insurance Rules

❓ What changed?

On September 14, 2026 (Reiwa 8), the Japan Pension Service posted an "Important Notice" announcing that the Ministry of Health, Labour and Welfare (MHLW) had issued two press releases the same day. They cover (1) how insured status is handled for sole proprietors and similar persons who are employed by an establishment as regular-type workers with short working hours, and (2) how insured status is handled for sole proprietors and similar persons who serve as officers of a corporation. Under Japan's Employees' Pension Insurance and Health Insurance, anyone "employed by" a covered establishment becomes an insured person. This is not limited to full-time staff under an employment contract: a company officer working under a delegation contract can also be insured if they receive remuneration for services from the corporation. By contrast, a sole proprietor running their own business is not an insured person for that business and instead belongs to the National Pension and National Health Insurance systems. The hard cases are people who hold both positions at once — running their own business while also working short hours as regular-type staff at another establishment, or while serving as a corporate officer. The two MHLW releases set out how insured status is treated in exactly these situations. The detailed content is in the MHLW releases, which are linked from the Japan Pension Service page.

👥 Who is affected?

• ●People running their own business while also working short hours as regular-type staff at another establishment
• ●Sole proprietors who also serve as officers (director, auditor, etc.) of a corporation
• ●Foreign residents who have filed a business opening notice and started a side or second business
• ●HR and administrative staff at establishments that employ or engage such people
• ●Anyone preparing a residence status renewal or permanent residency application who wants to confirm their insurance record

🌏 Impact on foreign residents

Plenty of foreign residents in Japan run their own business: officers of a company under the Business Manager status, people on Engineer/Specialist in Humanities status who filed a business opening notice and started a side business, or freelancers who also put in a few fixed hours at one particular company. All of them are in the situations these notices address. Which insurance system you belong to is not just about monthly premiums. It determines your future old-age pension amount, whether you can receive injury and sickness allowance (available to Health Insurance subscribers) when you cannot work, and whether your spouse or children can be registered as your dependants. On top of that, immigration screening for residence status renewal and permanent residency checks whether you have met public obligations such as taxes and social insurance premiums. If you assumed "I'm self-employed, so National Pension and National Health Insurance are enough" but were actually covered by Employees' Pension Insurance at your workplace — or the reverse — you may later face retroactive procedures and premium adjustments. Start by checking the reality of how you actually work.