年末調整 is Japan's system where employers reconcile employees' income tax each year-end. Similar to Korea's 연말정산.
Timeline
- **October**: Notify employees to prepare documents - **November**: Submit insurance certificates, mortgage info - **Early December**: Company aggregates - **December payroll**: Apply refunds/additional charges - **End of January**: File payment statements (源泉徴収票)
Key deductions
- Dependent, spouse - Social insurance premiums - Life and earthquake insurance premiums - Mortgage - Defined-contribution pension (iDeCo)
HR SaaS automation
- **SmartHR**: Year-end portal. Employees self-enter via smartphone. Auto-OCR on documents - **freee HR**: integrated with freee accounting - **jinjer**: Year-end module - **Jobcan**: Attendance-based integration
Practical tips
- December is typically fully allocated to year-end adjustment work - Handling it in Excel without HR SaaS: 50–80 hours for a 20-person team - Ex-employees/new hires need their previous employer's 源泉徴収票