💴 New Rule Cuts Social Insurance Premiums for 3 Years

❓ What is changing?

Under the FY2025 pension reform act (Act No. 74 of 2025), a "premium adjustment system" for health insurance and employees' pension insurance started in October 2026. Its purpose is to let short-time workers who have newly become subject to social insurance keep working without cutting back their hours or income just to avoid premium deductions. Under the system, the employer temporarily takes on part of the premium share that the insured employee would normally pay. This reduces the employee's own premium burden for a combined three years from the point the employer starts using the system. Until now there was no such relief: once a worker became subject to enrollment, the employee share was simply deducted from their pay. Two points matter. First, even though the employer temporarily covers part of the employee share, the total premium the employer ultimately pays does not increase. Second, the amount of pension the employee will receive in the future is not affected — the employees' pension enrollment record still builds up normally. Eligible workplaces are those that newly became a "voluntary specified covered workplace" (任意特定適用事業所) on or after October 1, 2026. Workplaces that become a "specified covered workplace" (特定適用事業所) through the expansion of social insurance coverage on or after October 1, 2027 are also covered.

👥 Who is affected?

• ●Short-time workers at a workplace that newly became a voluntary specified covered workplace on or after October 1, 2026
• ●Insured employees at a workplace that becomes a specified covered workplace through the coverage expansion on or after October 1, 2027
• ●Part-time and arubaito staff newly subject to health insurance and employees' pension insurance (foreign nationals are treated the same)
• ●Employers and HR staff at those workplaces — the system is applied by the employer, not the worker
• ●Short-time workers who have been limiting their hours or income because of premium deductions

🌏 Impact on foreign residents

Many foreign residents in Japan work part-time or arubaito hours. Once you become subject to social insurance, the employee share is deducted from your pay, so it is tempting to cut shifts to protect your take-home amount. At a workplace using the premium adjustment system, that burden is reduced for a combined three years instead. The key point is that lighter premiums do not mean a smaller pension later. Your employees' pension enrollment period and record stay intact, so the basis for your old-age pension — and for the lump-sum withdrawal payment if you eventually leave Japan — is not lost. Your status as an insured person under health insurance is also unchanged. The decision to use the system rests with the employer; there is no individual application by the worker. So the first step is to ask your HR or administration section whether your workplace newly became a voluntary specified covered workplace and whether it is using the adjustment system. Note that for students, the separate 28-hour-per-week limit under permission to engage in activity other than that permitted still applies — this system does not relax it.