Whether you are locally hired by a company in Japan or transferred to Tokyo by an overseas employer, your tax and social security responsibilities depend on bilateral agreements. Individuals hired locally in Japan are standardly enrolled in Japanese social security, whereas employees temporarily transferred for 5 years or less may remain under their home country's system if a bilateral treaty applies. Confirming these procedures with official institutions helps avoid double payments while working in Japan.
How does social security coverage work when working in Japan?
Without a bilateral social security agreement, foreign employees assigned to Japan might face dual coverage, contributing to both Japanese social security and their home country's system. When an agreement exists, coverage rules depend on your employment structure:
- Locally hired employees: Individuals hired directly by an employer in Japan are covered solely by the Japanese social security system.
- Temporary detachment (5 years or less): Employees sent to Japan by an employer in an agreement country for an expected duration of no more than 5 years are exempt from Japanese social security and remain covered by their home country's system.
- Long-term detachment (more than 5 years): If a transfer is expected from the start to exceed 5 years, the employee is enrolled in the Japanese system in principle.
- Unexpected extensions: If an assignment exceeds 5 years due to unforeseen circumstances, an extension of the exemption beyond 5 years may be applied for by the employer or self-employed worker, subject to specific treaty limits.
- Working in both countries simultaneously: Under agreements with the UK, South Korea, and Italy, individuals working in both countries during the same period are covered only by the pension system of their primary residence country.
- Self-employed individuals: Those temporarily working self-employed in Japan for up to 5 years remain under their home system, while those working longer than 5 years fall under the Japanese system.
For additional context on social security coverage rules, refer to the Japan Pension Service.
What are the conditions and document requirements for social security exemption?
To maintain coverage under your home country's system and remain exempt from Japanese social security during a temporary detachment, you must satisfy three essential conditions:
- You must maintain coverage under your home country's social security system throughout your assignment in Japan.
- You must remain employed by your employer in the agreement country, which continues to manage personnel matters and labor arrangements.
- Your expected assignment length in Japan must not exceed 5 years.
For accompanying family members, exemption rules vary depending on the agreement country and dependent status:
- Dependent exemption: In countries such as the United States, Germany, France, Canada, China, and South Korea, accompanying spouses and children registered as dependents are exempt from Japanese social security.
- Mandatory coverage: Under treaties with the United Kingdom and the Netherlands, there are no special provisions for dependents, making coverage under the Japanese system mandatory for accompanying family members.
- Required documentation: Exemption applications require a Certificate of Coverage issued by the home country's social security institute, along with a Certified Copy of Resident Registry (Juminhyo) or Resident Card verifying dependent status and relationship.
How do bilateral tax conventions prevent double taxation in Japan?
Japan maintains bilateral tax conventions with numerous partner jurisdictions to prevent double taxation on income and eliminate tax evasion, with updates documented as of June 26, 2026. Key agreements cover jurisdictions across the globe, including Australia, Canada, China, France, Germany, India, Italy, South Korea, the United Kingdom, and the United States.
Tax conventions set rules for income tax treatment depending on tax residency and employment arrangements. You can review the complete agreement status through the Ministry of Finance Japan.
What happens if you receive medical care outside Japan?
Foreign workers who reside long-term in Japan (generally over 5 years) and are enrolled in the Japanese health insurance system can file claims to cover eligible medical treatments received at hospitals outside Japan through their Japanese insurer.
Finding a place to stay
When preparing for an employment transfer or starting a new position in Tokyo, securing temporary housing prior to arrival allows you to complete municipal registration and administrative procedures smoothly. Many newcomers stay in a furnished monthly apartment first while completing their onboarding. OHAYO Stay offers furnished monthly apartments and rooms in Tokyo, giving arriving professionals a comfortable and hassle-free transition. Most homes have a minimum stay of 30 nights (shown on each listing), and the monthly price includes electricity, gas, water and Wi-Fi. This simple setup helps foreign workers focus on their job transition without worrying about setting up utility contracts.
FAQ
Do foreign workers hired directly by a Japanese company pay into Japanese social security?
Yes. Individuals locally hired by an employer in Japan are covered by the Japanese social security system under standard agreement rules.
How long can a temporarily transferred employee be exempt from Japanese social security?
An exemption is available for assignments expected to last no more than 5 years, provided the worker remains employed by their home country employer and covered by their home social security system.
Are accompanying family members automatically exempt from Japanese social security?
Not always. Exemption depends on the specific treaty terms and dependent status on the Resident Card or Juminhyo, whereas treaties with countries like the UK require mandatory Japanese coverage for dependents.
Sources
- 日本年金機構「Systems You Should Enroll in If You Work in Japan｜日本年金機構」(checked 2026-10-21)
- www.mof.go.jp「The List of Japan's Tax Conventions : Ministry of Finance」(checked 2026-10-21)
Facts are summarized in our own words; see the linked pages for the official details.
Rules and dates can change. Always confirm with the official source before you apply.