Social insurance when you hire or receive on secondment from Taiwan — there is no social security agreement between Japan and Taiwan

In short: When you hire, or receive on secondment, a person from Taiwan, they become an insured person under Japan's health insurance and employees' pension insurance regardless of nationality as long as they are ordinarily employed at an applicable workplace (employment insurance and workers' accident insurance also apply if requirements are met). The point to note is that there is no social security agreement between Japan and Taiwan.

Social security agreements coordinate coverage to prevent a double contribution burden and may provide for totalization of pension coverage periods. The systems covered and whether periods can be totalized depend on the agreement; the agreement with China does not provide for totalization. But Taiwan is not among the partner countries, so if the person remains enrolled in Taiwan's social insurance as well, there is no room to adjust that double burden by agreement. For HR staff of companies that hire or receive on secondment employees from Taiwan, this article organizes, from the viewpoint of a Shakai Hoken Roumushi, the application of Japan's social insurance and the concept of the double burden.

When you hire from Taiwan, what happens to Japan's social insurance?

The application of social insurance (health insurance and employees' pension insurance) is decided not by residence status or nationality but by whether the person is ordinarily employed at an applicable workplace. A person from Taiwan who is employed by a Japanese company, or seconded to work at a Japanese workplace, becomes an insured person the same as a Japanese worker if ordinarily employed and, for part-timers, meeting requirements such as the "three-quarters rule."

Insurance	How application is considered (the same for a person from Taiwan)
Health insurance / employees' pension	An insured person if ordinarily employed at an applicable workplace and meeting the three-quarters rule, etc. Nationality is not asked
Employment insurance	An insured person with 20 or more prescribed weekly hours (10 or more from October 2028) and expected employment of 31 days or more. Daytime students are excluded
Workers' accident insurance	Compulsorily applies to any business that employs even one worker. Applies to a worker regardless of nationality or residence status

For the three-quarters rule, see what happens to social insurance when you hire someone for short hours; for the whole picture of the procedures that move when you hire one foreign national, see how many windows do you need to hire one foreign national. On hiring and on separation, the notification of employment status of foreign nationals is generally required. People with the residence status “Diplomat” or “Official,” and special permanent residents, are exempt from this notification.

What double burden arises when there is no Japan–Taiwan agreement?

Social security agreements can provide for (1) prevention of a double pension contribution burden and (2) totalization of pension coverage periods. Agreements with some countries, including China, cover only the first function. According to the Japan Pension Service, agreements are in force with 24 countries (as of June 2, 2026), and Taiwan is not among them. The mechanism for preventing double enrollment under the agreement with China (the Japan–China social security agreement) is summarized in social insurance for staff stationed in or from China, but that mechanism cannot be used for Taiwan.

• Double enrollment can occur: if a person keeps their post at the Taiwanese company, is seconded to Japan, and remains enrolled in Taiwan's social insurance (such as labor insurance) while also becoming an insured person in Japan, premiums are charged on both sides. In an agreement country, a "certificate of coverage" can limit enrollment to one side, but Taiwan has no such certificate-of-coverage mechanism.
• Periods cannot be totalized: periods can be totalized only where the relevant agreement provides for it. The agreement with China has no such provision, and Japan and Taiwan have no agreement allowing totalization. Japanese periods are handled under the Japanese system and Taiwanese periods under the Taiwanese system, separately.
• Which system to enroll in is decided by each country's domestic law: with no agreement, if Japan's application requirements are met the person becomes a Japanese insured person, and the Taiwanese side is governed by Taiwanese law. Whether a double burden arises depends on the form of the secondment (under whose direction, and who bears the remuneration).

Whether a double burden actually arises must be confirmed by matching the content of the employment/secondment contract with the application of the Taiwanese system. Whether the Taiwanese system itself applies is a matter of judgment for the Taiwanese authorities and local professionals.

Can Taiwan's labor insurance and Japan's social insurance be adjusted?

Taiwan has social insurance systems such as labor insurance (勞工保險). There is no agreement to adjust premiums or enrollment periods between these and Japan's health insurance and employees' pension insurance. We therefore organize it as follows.

• Adjustment of premiums: there is no exemption or certificate of coverage under an agreement. As long as Japan's application requirements are met, Japanese premiums are charged in principle. Whether Taiwanese premiums are separately charged is governed by Taiwanese law.
• Receipt of pension: the record of employees' pension premiums paid in Japan is handled as a Japanese pension. If requirements are met it leads to a future pension, but if the person returns home after a short period of employment without meeting eligibility, consider the lump-sum withdrawal payment. For the flow, see when a foreign employee returns home, what happens to the pension. The lump-sum withdrawal payment is a system under which a person who has an insured period of, in principle, six months or more under employees' pension and returns home without the right to receive a pension may claim within two years after loss of qualification (in principle after leaving Japan); it can be claimed if requirements are met regardless of whether an agreement exists. However, because there is no agreement, Japanese and Taiwanese periods cannot be totalized.
• Medical care: health insurance covers medical care while working in Japan. The relationship with Taiwan's medical system is governed by Taiwanese law.

Thus, for Taiwan there is no option to "adjust by agreement," and the basic idea is that the Japanese system applies exactly according to Japan's requirements.

Who should you ask for payroll, taxation, and residence status?

When you receive a person from Taiwan, the responsible qualification is divided. Each becomes a separate contract.

What to do	Main person in charge
Application of Japan's labor and social insurance, qualification acquisition/loss notifications, maintaining employment contracts and work rules, payroll	Shakai Hoken Roumushi (our office)
Application, change, and renewal of residence status (application-agency service)	Gyoseishoshi
Income tax and the treatment of taxation between Japan and Taiwan	Tax accountant
Application of Taiwan's social insurance and tax	Taiwanese authorities / local professionals
Labor disputes and legal judgments over contracts	Attorney

Have a question about your situation?

Tell us about your social insurance, payroll or employment enquiry.

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There is no formal tax treaty between Japan and Taiwan; there is a framework that responds under domestic law based on a private arrangement, but its application is the domain of a tax accountant. The application and agency service for residence status can be connected to 四葉行政書士事務所, but 四葉行政書士事務所 is a separate, independent entity from our office, and the Shakai Hoken Roumushi work and the Gyoseishoshi work are contracted separately (we do not take on both under one engagement). Our office does not receive referral fees.

What should a company prepare before receiving a person?

For secondment, whether a double burden arises changes with the form of the secondment, so organizing the following at the contract stage makes later procedures smoother.

• Make the form of employment/secondment clear in writing: clarify in the contract under whose direction the person works and who bears the remuneration. The application of Japan's social insurance is judged by the actual employment relationship.
• Project wages and premiums on the premise of Japanese insured-person status: estimate labor costs incorporating the burden of Japanese health insurance, employees' pension, employment insurance, and workers' accident insurance. Whether a Taiwanese burden remains is confirmed under Taiwanese law.
• Fix the residence status and working conditions early: obtaining residence status is the business of a Gyoseishoshi. Working conditions must be disclosed in writing as an employer's obligation, and the same rules as for Japanese workers apply.

四葉社会保険労務士事務所 can advise on organizing the application of Japan's social insurance, qualification acquisition/loss notifications, payroll, and maintaining employment contracts and work rules. Consultation is free, and fees are summarized in the fee schedule.

Frequently asked questions

Q. Is there a social security agreement between Japan and Taiwan?
A. No. Taiwan is not among the partner countries of the social security agreements published by the Japan Pension Service (24 in force, as of June 2, 2026). Neither coordination of coverage nor totalization under an agreement is available between Japan and Taiwan. The agreement with China, by comparison, prevents a double contribution burden but does not provide for totalization.

Q. If we receive a person on secondment from a Taiwanese company, what happens to Japan's social insurance?
A. If ordinarily employed at an applicable Japanese workplace and meeting the requirements, the person becomes an insured person under Japan's health insurance and employees' pension insurance regardless of nationality. If they remain enrolled in Taiwan's social insurance, a double burden may arise, but there is no mechanism to adjust it because there is no agreement. Whether a double burden arises depends on the form of the secondment (direction and remuneration).

Q. Can the period paid into Taiwan's pension and the Japanese period be totalized?
A. No. Totalization of enrollment periods is done under a social security agreement, but because there is no agreement between Japan and Taiwan, Japanese periods are handled under the Japanese system and Taiwanese periods under the Taiwanese system, separately. If the person returns home without meeting Japanese eligibility, consider the lump-sum withdrawal payment.

Q. Can a Taiwanese employee who returns home after a short period receive the lump-sum withdrawal payment?
A. A person who has an insured period of, in principle, six months or more under employees' pension and returns home without the right to receive a pension may be able to claim a lump-sum withdrawal payment within two years after loss of qualification (in principle after leaving Japan). This is a system that can be claimed if requirements are met, regardless of whether an agreement exists. Check the amount and the claim method in the Japan Pension Service guidance.

Sources

• Application of health insurance and employees' pension: a person ordinarily employed at an applicable workplace is an insured person regardless of nationality or residence status. Part-timers enroll in principle if their prescribed working hours and days are at least three-quarters of those of a regular worker (Health Insurance Act, Employees' Pension Insurance Act; Japan Pension Service).
• Employment insurance insured-person requirements: 20 or more prescribed weekly hours (10 or more from October 1, 2028 (Reiwa 10) under Act No. 26 of 2024) and expected employment of 31 days or more. Daytime students are excluded in principle (Employment Insurance Act).
• Application of workers' accident insurance: compulsorily applies to a business that employs workers and applies to a worker regardless of nationality or residence status (Industrial Accident Compensation Insurance Act).
• Ministry of Health, Labour and Welfare: notification of foreign-national employment: “Diplomat,” “Official,” and special permanent residents are exempt from this notification. Accessed 14 September 2026.
• MHLW: Status of social security agreements (24 agreements in force as of 2026-06-02); Japan Pension Service: Effective dates and covered systems (no totalization under the agreement with China; Taiwan is not listed as an agreement partner). Accessed 2026-09-14.
• Certificate of coverage: issued by the Japan Pension Service to allow a person, for temporary assignment (often within five years) with an agreement partner country, to remain enrolled in only one system. There is no certificate-of-coverage mechanism for Taiwan, which has no agreement (Japan Pension Service).
• Lump-sum withdrawal payment: a person who has an insured period of, in principle, six months or more under employees' pension and returns home without the right to receive a pension may claim within two years after loss of qualification (in principle after leaving Japan). Because there is no agreement, Japanese and Taiwanese periods cannot be totalized (Japan Pension Service).
• Taxation between Japan and Taiwan: there is no formal tax treaty between Japan and Taiwan; there is a framework that responds under domestic law based on a private arrangement. The taxation of income tax is the business of a tax accountant and is not covered in this article.
• Business of a Shakai Hoken Roumushi: Article 2 of the Certified Social Insurance and Labor Consultant Act.

This article does not decide whom to consult. 四葉社会保険労務士事務所 can advise on the application of Japan's labor and social insurance, qualification acquisition/loss notifications, payroll, and maintaining employment contracts and work rules. The application and change of residence status (application-agency service) are the business of a Gyoseishoshi, income tax and the treatment of taxation between Japan and Taiwan are the business of a tax accountant, the application of Taiwan's social insurance and tax is a matter for the Taiwanese authorities and local professionals, and labor disputes are the business of an attorney. The Shakai Hoken Roumushi work and the Gyoseishoshi work are contracted separately as separate, independent entities. Our office does not receive referral fees. The final decision on whether Japan's social insurance applies in an individual case, or whether a double burden arises, is made by the pension office and the Japan Pension Service. For fees when consulting 四葉社会保険労務士事務所, see the fee schedule; for frequently asked questions, see the FAQ.

This article is general information. Individual judgments, such as the application of social insurance and whether a double burden arises, are made by a qualified professional after a consultation, in light of the latest primary sources (the Ministry of Health, Labour and Welfare, the Japan Pension Service, etc.) and individual circumstances. Written by Joji Uramatsu (Shakai Hoken Roumushi, Gyoseishoshi, Registered Real Estate Transaction Specialist).