Social insurance for staff posted to China — avoiding double pension cover under the Japan–China Social Security Agreement

Bottom line first: Post an employee to China and, as long as the employment relationship with the Japanese company continues, their Japanese employees' pension cover remains, while China also requires enrolment in its employees' basic old-age insurance — so pension contributions can arise twice. The mechanism that avoids this is the Japan–China Social Security Agreement, in force since 1 September 2019.

The agreement covers pension only. For a temporary posting of up to five years, a certificate of coverage issued by the Japan Pension Service lets the worker, in principle, stay only in the Japanese pension system. Health insurance is not covered, so cover under the Chinese medical system has to be considered separately.

Status-of-residence applications and filing agency work belong to a Gyoseishoshi; income tax and tax-treaty matters to a tax accountant. What this office takes on is the social and labour insurance procedures; whether the agreement applies in a given case is judged by a qualified professional after a consultation.

What double burden arises if the worker stays in Japanese employees' pension while in China?

Even where a Japanese company posts an employee to China, as long as that employee remains in an employment relationship with the Japanese company, their Japanese employees' pension and health insurance cover in principle remains. Article 9 of the Employees' Pension Insurance Act provides that "a person under 70 years of age who is employed at an applicable workplace is an insured person of employees' pension insurance"; cover does not lapse merely because the place of work is abroad.

Meanwhile, China requires employees to enrol in basic old-age insurance (employees' basic old-age insurance). Without the agreement, pension contributions arise in both Japan and China for the same employee. That is the double-enrolment problem.

Where it arises	Without the agreement	With the agreement (temporary posting of up to five years)
Japanese employees' pension	Enrolled while employment continues	Continues
Chinese employees' basic old-age insurance	Enrolment required	Exempt under the certificate of coverage
Result	Pension contributions in both countries	In principle Japan only

This concerns pension only. China's medical, work-injury and unemployment insurance are outside the agreement and follow the local system.

What, and how far, does the Japan–China Social Security Agreement cover?

It covers public pension only. It does not include health insurance. Getting this wrong leads to the misunderstanding that "there is an agreement, so nothing need be paid in China".

	Japan side	China side
Systems covered	National Pension (excluding the National Pension Fund) and Employees' Pension Insurance (excluding the Employees' Pension Fund)	Employees' basic old-age insurance
Systems not covered	Health insurance, long-term care insurance, workers' accident insurance, employment insurance	Medical insurance, work-injury insurance, unemployment insurance and the like

The agreement was signed in May 2018 and came into force on 1 September 2019. The basic principle is enrolment in the pension system of the country of work; the exception is that, for a temporary posting of up to five years, the worker may stay enrolled only in the system of the sending country.

On medical cover, Japanese health insurance in principle remains while the employment relationship with the Japanese company continues, but there are situations where separate enrolment in the Chinese medical system is also required. Design local medical cover separately from the agreement.

When, where and how is the certificate of coverage applied for?

For a temporary posting from Japan to China, the certificate of coverage proves that the worker stays enrolled only in the Japanese pension system. It is issued by the Japan Pension Service.

Item	Content
What it certifies	That the worker remains enrolled in the Japanese pension system and is exempt from Chinese employees' basic old-age insurance
Where to apply	The Japan Pension Service (administrative centre and the like)
Postings covered	Temporary postings of, in principle, up to five years
How it is used	The issued certificate is presented on the China side to obtain the exemption

Where a posting is expected from the outset to exceed five years, it does not fall within this temporary-posting framework. The treatment of a posting initially planned for up to five years but then extended is left to agreement between the implementing agencies of the two countries, so it turns on the individual circumstances. Confirm the actual application form, filing point and processing time against the latest Japan Pension Service guidance immediately before applying.

How does hiring a Chinese national in Japan differ from posting a Japanese to China?

The direction changes whose certificate is used. Confusing this means dealing with the wrong counterparty.

Situation	System that continues	Certificate used
A Japanese company temporarily posts a Japanese or Chinese employee to China	Japanese employees' pension	Certificate of coverage issued by the Japan Pension Service
A Chinese company temporarily posts a Chinese employee to Japan	Chinese employees' basic old-age insurance	Certificate of coverage issued by the Chinese implementing agency
A Japanese company newly hires a Chinese national in Japan (local hire)	Japanese employees' pension and health insurance	The agreement's certificate does not apply (ordinary insured person)

Note the third. A Chinese national locally hired in Japan enrols in Japanese employees' pension and health insurance as an ordinary insured person employed by the Japanese company. The agreement is engaged only where someone is temporarily posted from one country to the other. On the pension of a foreign employee who returns home, see When a foreign employee returns home, what happens to their pension (lump-sum withdrawal).

Who should handle the social insurance, the status of residence and the tax?

Even within one case, the responsible entities are separate.

Issue	In charge
Social and labour insurance determination and the certificate of coverage application	Shakai Hoken Roumushi (this office)
Status-of-residence application, change and filing agency work	Gyoseishoshi (filing agent)
Income tax, resident tax, tax-treaty treatment, tax administrator	Tax accountant
Details of the local (Chinese) social insurance and tax	Local professional

Status-of-residence applications are Gyoseishoshi work. 四葉行政書士事務所 is a business entity independent of this office; where needed, we introduce it under a separate contract that you conclude directly, and this office takes no referral fee. On injuries while working abroad, see Overseas business trips and overseas assignments are entirely different for workers' accident cover.

What can 四葉社会保険労務士事務所 do?

What this office takes on is the following social and labour insurance procedures and organising work.

• Organising the treatment of employees' pension and health insurance cover for staff posted to China
• Supporting the certificate-of-coverage application under the Japan–China Social Security Agreement
• Organising the determination for staff received on temporary posting from China
• Enrolment procedures where a Chinese national is locally hired in Japan
• Designing the practice of payroll and deduction of social insurance contributions

The following are not handled here.

• Status-of-residence application, change and filing agency work → 四葉行政書士事務所 accepts this as a separate business entity
• Income tax, tax treaties and tax administrator work → we connect you with a tax accountant (Zeirishi)
• Specific procedures for social insurance and tax within China → we introduce a local professional
• Leases of premises or company housing → 四葉不動産株式会社 accepts this as a separate business entity

四葉不動産株式会社, 四葉行政書士事務所 and 四葉社会保険労務士事務所 each accept work as an independent business entity, under a separate contract. Where another professional is introduced, you contract with them directly, and this office receives no referral fee.

Consultations are free of charge. Fees are set out in the fee schedule; see also our services and how a consultation proceeds.

Frequently asked questions

Q. Can Japanese health insurance still be used while posted to China?
A. As long as the employment relationship with the Japanese company continues, Japanese health insurance cover in principle remains. But health insurance is not covered by the Japan–China Social Security Agreement, so cover under the Chinese medical system has to be considered separately. Design how treatment and medical costs are handled locally separately from the agreement. Whether it applies in a given case is judged by a qualified professional after a consultation.

Q. With a certificate of coverage, need nothing at all be paid in China?
A. No. What the certificate exempts is only the pension the agreement covers (Chinese employees' basic old-age insurance). China's medical, work-injury and unemployment insurance are outside the agreement and follow the local system. The idea that "there is an agreement, so nothing is paid in China" is wrong.

Q. What happens if the posting exceeds five years?
A. A temporary posting of up to five years is the premise for staying enrolled only in the sending country's system. A posting expected from the outset to exceed five years does not fit this framework. The treatment of a posting initially planned for up to five years but then extended is left to agreement between the two countries' implementing agencies and turns on the circumstances. This article does not reach a single conclusion.

Q. We hired a Chinese national in Japan. Is any agreement procedure needed?
A. Where a Japanese company hires locally in Japan, that employee enrols in Japanese employees' pension and health insurance as an ordinary insured person employed by the Japanese company; the agreement's certificate does not apply. The agreement is engaged only where someone is temporarily posted from one country to the other, such as a posting from a Chinese company to Japan.

Basis for this article

• Agreement between the Government of Japan and the Government of the People's Republic of China on Social Security — signed May 2018, in force 1 September 2019. Covers public pension (Japan side: National Pension and Employees' Pension Insurance, excluding the respective funds; China side: employees' basic old-age insurance). Health insurance is not covered. A temporary posting of up to five years is enrolled, in principle, only in the sending country's pension system (confirmed on 22 August 2026 from the Ministry of Health, Labour and Welfare, the Japan Pension Service and public materials)
• Certificate of coverage — for a temporary posting from Japan to China, the document proving continued enrolment in the Japanese pension system; issued by the Japan Pension Service; presented on the China side to obtain exemption from employees' basic old-age insurance (confirmed on 22 August 2026 from Japan Pension Service guidance)
• Employees' Pension Insurance Act (Act No. 115 of 1954) Article 9 — "a person under 70 years of age who is employed at an applicable workplace is an insured person of employees' pension insurance"; cover in principle continues during overseas work where the employment relationship with the Japanese company continues (confirmed on 22 August 2026 on e-Gov)
• Health Insurance Act (Act No. 70 of 1922) Article 3, paragraph 1 — definition of insured person; health insurance is outside the Japan–China Social Security Agreement (confirmed on 22 August 2026 on e-Gov)
• Certified Social Insurance and Labour Consultant Act (Act No. 89 of 1968) Article 2, paragraph 1, items 1, 1-2 and 3
• The specific enrolment procedures for Chinese employees' basic old-age insurance and medical insurance, and how the certificate is presented and accepted in China, depend on the local system and practice. The treatment for a particular company or posting is not covered here (unverified)
• The specific application form, filing point and processing time for the certificate of coverage should be confirmed against the latest Japan Pension Service guidance immediately before applying (unverified)

This article is general information. Individual determinations are made by a qualified professional after a consultation, in light of individual circumstances. 四葉社会保険労務士事務所 can advise on organising employees' pension and health insurance cover for staff posted to China, supporting the certificate-of-coverage application under the Japan–China Social Security Agreement, organising the determination for staff received on temporary posting from China, and enrolment where a Chinese national is locally hired in Japan. Status-of-residence applications and filing agency work are accepted by 四葉行政書士事務所 as a separate business entity, income tax and tax-treaty work by a tax accountant, and procedures within China by a local professional, each contracted separately. Leases of premises or company housing are accepted by 四葉不動産株式会社 as a separate business entity. If a different professional is needed, each is contracted separately, and there is no referral fee. Frequently asked questions are collected in the FAQ. Written by Joji Uramatsu (Shakai Hoken Roumushi, Gyoseishoshi, Registered Real Estate Transaction Specialist).