Health Insurance When Changing Jobs in Japan

Health insurance job change in Japan runs as an employer to employer handoff, not a reapplication by the worker.¹² The old employer closes the prior qualification and the new employer opens the next one, while the worker returns one proof and presents two identity details.

Confirm current details with official sources

Procedures, fees, and requirements can change. Confirm current details at the Japan Pension Service and the Ministry of Health, Labour and Welfare (MHLW). This article is general information, not medical advice; for decisions about your own care, consult a licensed healthcare provider.

Overview

Japan assigns public health insurance by employment status rather than letting workers choose a scheme.³ Salaried employees belong to Employees' Health Insurance through their employer, while residents outside employer coverage belong to National Health Insurance at the municipality.³

This article covers the direct move between two covered employers. It walks through the last-day return, the loss filing, the first-day documents, the acquisition filing, proof timing, and gap handling.¹²

Who this covers

This guide covers salaried employees who leave one covered workplace and join another without a long unemployment spell.¹ Foreign nationals permitted to work under their status of residence are covered on the same terms as Japanese nationals.²

It also covers part-time workers who meet the coverage line. The rule and its fallback are described under the new-employer filing below.²

What ends at the old employer

The old employer's filing ends the prior qualification. The worker's job is to hand back the old proof and keep the leaving papers that show the end date.¹

Return the proof of coverage on the last day

Return the proof issued under the prior employer on the last day so it cannot be used after eligibility ends.⁴ Where a former plastic card or an Eligibility Confirmation Form was issued, hand it to the prior employer or follow the employer's return instruction.

The proof landscape has changed. New issuance of former plastic cards stopped on 2024-12-02, and all former cards expired by 2025-12-01 (as of 2026-09-07; confirm current details with MHLW).⁴ Reception now runs through the マイナ保険証 (maina hokenshō, "health-insurance-use-registered My Number Card") or the 資格確認書 (shikaku kakuninshō, "Eligibility Confirmation Form").⁴

Do not reuse the old proof after the leaving date

Eligibility ends with the loss filing even when the physical proof is still in hand. A visit billed to the prior insurer after that date can come back as a repayment request.¹⁴

The loss-of-eligibility filing

The 資格喪失届 (shikaku sōshitsu todoke, "loss-of-eligibility notice") is the employer's report that closes the old qualification.¹ Coverage through the prior insurer runs until the date on that filing.

Ask the prior employer for the leaving documents that record the date. Those papers speed every later step, including a ward-office fallback if the next job starts later than planned.¹

What starts at the new employer

The new employer's filing opens the next qualification. The worker's job is to present identity and pension details on day one so the filing can go out promptly.²

Bring on the first day	Why the employer needs it
Residence card	Confirms identity and work permission for the enrollment record2
Basic Pension Number details (Basic Pension Number Notice)	Reuses the single lifelong pension number across employers2

The table above covers the standard first-day pair. The number itself never changes across job moves, so the new employer reuses it rather than issuing a new one.²

What to present on the first day

Present the residence card and the Basic Pension Number details at the new employer's onboarding counter.² The 基礎年金番号 (kiso nenkin bangō, "Basic Pension Number") is the lifelong identifier that links the health and pension enrollment records.

Keep the notice in a safe place across moves. A missing notice slows the filing while the number is reconfirmed.²

Employer filing deadline

The new employer submits the Application to Enroll in Employees' Pension Insurance and Employees' Health Insurance within 5 days after employment.² The destination is the Japan Pension Service branch office or processing center covering the company.²

Part-time workers are covered when weekly hours and monthly days reach three-fourths or more of regular workers in the same workplace.² Workers below that line are still covered when all five conditions hold, including a monthly wage of ¥88,000 or more (as of 2026-03-02; confirm current figures with the Japan Pension Service).²

Coverage is compulsory once the line is met

Neither the employer nor the worker can opt in or out once the workplace and hours tests are met. The filing is a legal duty, not a contract choice.²

Proof of coverage during the switch

Proof arrives after eligibility starts. The gap between the filing date and the arrival of the new proof is normal, and clinics have a path for it.⁴⁵

The switch from old proof to new proof looks like this:

The diagram above shows the handoff as a single chain.¹²⁴ Each employer files its own end, and the worker carries only the return and the first-day documents.

New proof timing

Practitioner sources describe the new proof as typically arriving 1 to 4 weeks after the acquisition filing (as of 2026-09-07; confirm current timing with the new insurer).⁴ The exact document name varies by insurer, since Kyokai Kenpo and Health Insurance Societies administer their own proof.

Where Maina-Hokensho is already registered, online qualification confirmation updates once the new enrollment is recorded.⁴⁵ No new plastic card is collected, because the My Number Card itself acts as the insurance card once use registration is done.⁴

Urgent care before the new proof arrives

For urgent care before the new proof arrives, ask the new insurer about a temporary document.⁵ Where no document is ready, the clinic can handle the visit as a pre-card claim that is settled once qualification is confirmed.

Without proof at the desk, the patient pays the full scheduled amount first and reclaims the insured share afterward with receipts.⁵ Keep every receipt and the visit details until the new qualification is recorded.

Ask for the temporary proof before booking non-urgent visits

A short call to the new insurer before a planned visit often produces the temporary document or a clear claim instruction. That call costs less time than a full-payment reclaim later.⁵

Gap coverage between insurers

A direct move rarely produces a true uninsured gap. The two filings meet in the middle, and retroactive recording closes the seam.¹²

When the old coverage ends and the new one begins

Coverage runs through the prior insurer until the date on the prior employer's loss notice.¹ Coverage through the new insurer starts from the acquisition-notice date.²

The counter math does not change across the switch. Working-age patients pay the same 30 percent share under either insurer, because benefit packages are essentially identical across schemes.³

What to do if there is a blank period

A direct employer to employer move is handled by retroactive qualification once both filings are recorded.¹² Keep receipts for any interim visit so the correct insurer can settle its share.

A blank period with no new employer is different. Enroll at the municipal counter for National Health Insurance rather than waiting uninsured for the next job.¹³ The municipal track becomes the fallback the day employer coverage ends.¹

Good to know

Keep using the old proof after the last day can create a repayment

Using the prior employer's proof after the loss date can lead the prior insurer to reclaim the paid share.¹⁴ Eligibility ends with the filing, not when the proof is physically collected. Return the proof on schedule and use the new qualification path for later visits.¹

A late acquisition filing delays the new proof but not the eligibility date

A late employer filing delays the arrival of the new proof but does not move the eligibility start date once recorded.² The 5-day employer deadline ties enrollment to the employment facts, not to the paper's arrival day. Workers who need care during the wait should use the temporary-document or reclaim path above.²⁵

A gap with no new employer means a ward-office visit, not waiting

Workers with no immediate new employer move to National Pension and National Health Insurance through the municipal counter.¹ Waiting uninsured leaves interim bills fully out of pocket until enrollment is filed. The termination papers from the former employer speed that counter visit.¹

See also

• Tenshoku Procedure: The Job-Change Sequence
• Notifying Immigration of the Employer Change
• The High-Cost-Catch (Kogaku Ryoyohi) System
• Shakai Hoken Overview
• Continuation After Resignation: Nin-i Keizoku
• The Dependent (Fuyo) System

References

Footnotes

1. Japan Pension Service (JPS). "Employment / Job change / Retirement" (English). Last updated 2026-03-02. https://www.nenkin.go.jp/international/english/scene/job/index.html ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶ ↩¹⁷

2. Japan Pension Service (JPS). "Enrollment in Employees' Pension Insurance and Employees' Health Insurance" (English). Last updated 2026-03-02. https://www.nenkin.go.jp/international/english/japanese-system/employeespension/epi_procedure.html ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶ ↩¹⁷ ↩¹⁸ ↩¹⁹ ↩²⁰ ↩²¹

3. Japan Health Policy NOW (Health and Global Policy Institute). "3.1 Japan's Health Insurance System." https://japanhpn.org/en/section-3-1/ ↩ ↩² ↩³ ↩⁴

4. 厚生労働省 (MHLW). 「マイナンバーカードの健康保険証利用（マイナ保険証）について」. https://www.mhlw.go.jp/stf/newpage_08277.html ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰

5. 厚生労働省 (MHLW). 「高額療養費制度を利用される皆さまへ」. Updated 2026-07-31. https://www.mhlw.go.jp/stf/seisakunitsuite/bunya/kenkou_iryou/iryouhoken/juuyou/kougakuiryou/index.html ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶