Japan Nenmatsu Chosei (年末調整)
Year-end tax adjustment for Japan — dependent and insurance deductions, NTA income-tax reconciliation and gensen choshuhyo (源泉徴収票) withholding statements
Run the Japanese year-end tax adjustment directly in Odoo. At year end the employer reconciles the income tax withheld each month against each employee's actual annual liability under National Tax Agency (国税庁) rules, refunds or collects the difference, and issues the 源泉徴収票 withholding statement. Built on Japan's hr module with no Enterprise payroll dependency.
Full deduction engine
Computes the employment-income deduction (給与所得控除), the tapered basic deduction (基礎控除), the spouse and spouse-special deduction (配偶者控除 / 配偶者特別控除), dependent deductions (扶養控除) and the life- and earthquake-insurance deductions — all from editable statutory defaults.
Income tax & surtax
Applies the progressive national income-tax table and the 2.1% reconstruction special income tax (復興特別所得税), then reconciles the annual tax (年調年税額) against the tax already withheld to show the refund (還付) or collection (徴収) due per employee.
Gensen choshuhyo (BYOK)
Issues the 源泉徴収票 withholding statement for every employee and exports the batch as a CSV feed with the My Number masked — ready to upload to your own e-Tax / eLTAX 給与支払報告書 channel. The module sends nothing itself.
My Number validation
Real check-digit validators: the modulus-11 個人番号 (12-digit My Number) and the modulus-9 法人番号 (13-digit Corporate Number) algorithms, on the company, employees and dependents. My Numbers are masked to their last four digits on statements.
Highlights
- Year-end adjustment runs with per-employee reconciliation lines.
- Dependent register (一般 / 特定 / 老人 / 同居老親) per employee.
- Onboarding wizard for Corporate Number, surtax rate and basic deduction.
- Authority: National Tax Agency (国税庁).
Compatible with Odoo 18 and Odoo 19 Community and Enterprise. License OPL-1.
Disclosure: this module produces withholding statements and their CSV feed locally for you to file. No data is transmitted anywhere by the module itself.
Screenshots
Year End Adjustment Run 202
Year End Adjustment Line Tar
Year End Adjustment Lines Pe
Update date: 2026-07-02