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openaccountants/skills/japan-payroll.md

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1---
2name: japan-payroll
3description: >
4 Use this skill whenever asked about Japanese payroll, income tax withholding
5 (源泉徴収 gensen chōshū), social insurance (社会保険 shakai hoken), labour
6 insurance (労働保険 rōdō hoken), or employer obligations in Japan. Trigger on
7 phrases like "gensen choshu", "源泉徴収", "shakai hoken", "社会保険",
8 "厚生年金", "kosei nenkin", "kenko hoken", "健康保険", "雇用保険",
9 "koyou hoken", "労災保険", "rosai hoken", "年末調整", "nenmatsu chousei",
10 "year-end adjustment", "standard monthly remuneration", "hyōjun hōshū getsugaku",
11 "payslip Japan", "給与明細", "kyūyo meisai", "minimum wage Japan",
12 "overtime Japan", "36 agreement", "子ども・子育て支援金",
13 or any question about running payroll in Japan. ALWAYS read this skill before
14 processing any Japanese payroll work.
15version: 1.0
16jurisdiction: JP
17category: payroll
18depends_on:
19 - payroll-workflow-base
20---
21 
22# Japan -- Payroll Skill v1.0 (日本の給与計算)
23 
24---
25 
26## Section 1 -- Quick Reference
27 
28| Field | Value |
29|---|---|
30| Country | Japan (日本国) |
31| Currency | JPY (¥) only |
32| Tax year (income tax) | Calendar year (1 January -- 31 December) |
33| Fiscal year (social insurance) | 1 April -- 31 March |
34| Primary legislation | Income Tax Act (所得税法); Labour Standards Act (労働基準法); Health Insurance Act (健康保険法); Employees' Pension Insurance Act (厚生年金保険法); Employment Insurance Act (雇用保険法) |
35| Tax authority | National Tax Agency (国税庁 NTA) |
36| Social insurance authority | Japan Pension Service (日本年金機構); prefecture health insurance associations |
37| Reporting system | 源泉徴収税額表 (withholding tax tables); 年末調整 (year-end adjustment) |
38| Pay frequency | Monthly (most common, typically 25th or end of month) |
39| Employer registration | Tax office (源泉徴収義務者) + Japan Pension Service + Hello Work (ハローワーク) |
40| Validated by | Pending -- requires sign-off by a Japanese certified tax accountant (税理士) or social insurance labour consultant (社会保険労務士) |
41| Skill version | 1.0 |
42 
43---
44 
45## Section 2 -- Income Tax Withholding (源泉徴収)
46 
47Japanese employers withhold income tax monthly using the NTA's published withholding tax tables (源泉徴収税額表 -- monthly table / 月額表). The tables include the 2.1% reconstruction surtax (復興特別所得税, in effect through 31 December 2037).
48 
49### Withholding Table Categories
50 
51| Column | Japanese | Criteria |
52|---|---|---|
53| 甲 (Kō) | Primary employer | Employee has submitted 扶養控除等申告書 (dependency exemption declaration) |
54| 乙 (Otsu) | Secondary employer | No declaration filed; flat 3.063% minimum or table rate |
55 
56The 甲 table uses the employee's number of dependents (扶養親族等の数) to determine the withholding amount from a lookup table, not a formula.
57 
58### Reference: Individual Income Tax Brackets (Annual)
59 
60These are the annual rates applied at year-end adjustment (年末調整) or final return (確定申告). Monthly withholding approximates these progressively.
61 
62| Taxable Income (JPY) | Rate | Deduction |
63|---|---|---|
64| 0 -- 1,950,000 | 5% | ¥0 |
65| 1,950,001 -- 3,300,000 | 10% | ¥97,500 |
66| 3,300,001 -- 6,950,000 | 20% | ¥427,500 |
67| 6,950,001 -- 9,000,000 | 23% | ¥636,000 |
68| 9,000,001 -- 18,000,000 | 33% | ¥1,536,000 |
69| 18,000,001 -- 40,000,000 | 40% | ¥2,796,000 |
70| 40,000,001+ | 45% | ¥4,796,000 |
71 
72Plus 2.1% reconstruction surtax on calculated tax. Plus separate resident tax (住民税) at approximately 10% (municipal + prefectural), withheld from June of the following year.
73 
74### Employment Income Deduction (給与所得控除 -- 2026)
75 
76| Gross Employment Income (JPY) | Deduction |
77|---|---|
78| Up to 1,625,000 | ¥650,000 (minimum, raised from ¥550,000 in 2026) |
79| 1,625,001 -- 1,800,000 | Income × 40% - ¥100,000 |
80| 1,800,001 -- 3,600,000 | Income × 30% + ¥80,000 |
81| 3,600,001 -- 6,600,000 | Income × 20% + ¥440,000 |
82| 6,600,001 -- 8,500,000 | Income × 10% + ¥1,100,000 |
83| 8,500,001+ | ¥1,950,000 (cap) |
84 
85### Year-End Adjustment (年末調整)
86 
87Employers must perform nenmatsu chōsei in December for all 甲 employees. This reconciles monthly withholding to the actual annual tax liability, accounting for insurance deductions, spouse/dependent deductions, and housing loan credits. The employer refunds or collects the difference in the December (or January) payroll.
88 
89---
90 
91## Section 3 -- Social Security: Employee Deductions (社会保険 / 労働保険)
92 
93Japanese social insurance premiums are split approximately 50/50 between employer and employee (except workers' compensation which is employer-only and child allowance contribution which was employer-only until 2026).
94 
95### Employee Share of Social Insurance (2026)
96 
97| Premium | Employee Rate | Basis | Ceiling |
98|---|---|---|---|
99| Health insurance (健康保険) | ~4.925% (Tokyo) | Standard monthly remuneration (SMR) | Grade 50: ¥1,390,000/month |
100| Long-term care insurance (介護保険) | ~0.810% | SMR | Same as health; ages 40--64 only |
101| Welfare pension (厚生年金) | 9.150% | SMR | Grade 32: ¥650,000/month |
102| Employment insurance (雇用保険) | 0.50% (from Apr 2026) | Total wages | No ceiling |
103| Child-rearing support (子ども・子育て支援金) | 0.115% (from Apr 2026) | SMR | Same as health |
104 
105**Health insurance rates vary by prefecture and insurer.** The Tokyo rate shown (9.85% total / 4.925% employee) is illustrative. Each prefecture's Kyōkai Kenpō (協会けんぽ) publishes its own rate.
106 
107### Standard Monthly Remuneration (標準報酬月額)
108 
109Social insurance premiums are based on the SMR, a standardised salary grade (not actual pay). SMR is determined in September each year (算定基届 santei kiso todoke) based on April--June average earnings. Changes mid-year only occur with significant salary changes (随時改定 zuiji kaitei -- ≥2 grade change sustained over 3 months).
110 
111### Bonus Premiums
112 
113Social insurance premiums also apply to bonuses at the same rates, subject to annual caps:
114- Health insurance: ¥5,730,000 cumulative annual cap on bonus
115- Welfare pension: ¥1,500,000 per single bonus payment
116 
117---
118 
119## Section 4 -- Social Security: Employer Contributions
120 
121### Employer Share of Social Insurance (2026)
122 
123| Premium | Employer Rate | Notes |
124|---|---|---|
125| Health insurance (Tokyo) | ~4.925% | Same as employee |
126| Long-term care insurance | ~0.810% | Same as employee (ages 40--64) |
127| Welfare pension | 9.150% | Same as employee |
128| Child allowance contribution (子ども・子育て拠出金) | 0.360% | Employer-only; on SMR |
129| Child-rearing support (子ども・子育て支援金) | 0.115% | From Apr 2026; same as employee |
130| Employment insurance | 0.85% (from Apr 2026) | Higher than employee share |
131| Workers' compensation (労災保険) | 0.30% (typical office) | Employer-only; rate varies by industry (0.25%--8.8%) |
132 
133### Total Indicative Employer Cost (2026, Tokyo, Age 40--64)
134 
135| Component | Rate |
136|---|---|
137| Health + long-term care | 5.735% |
138| Welfare pension | 9.150% |
139| Child allowance + child-rearing support | 0.475% |
140| Employment insurance | 0.850% |
141| Workers' compensation (office) | 0.300% |
142| **Total employer social insurance** | **~16.51%** |
143 
144For employees under 40 (no long-term care): approximately 15.70%.
145 
146---
147 
148## Section 5 -- Minimum Wage and Overtime
149 
150### Minimum Wage
151 
152Japan has no single national minimum wage. Each prefecture sets its own rate annually (effective October). The national weighted average reached ¥1,121/hour in October 2025.
153 
154| Prefecture | Rate (JPY/hour, Oct 2025) |
155|---|---|
156| Tokyo | ¥1,163 |
157| Kanagawa | ¥1,162 |
158| Osaka | ¥1,114 |
159| Aichi | ¥1,077 |
160| Fukuoka | ¥1,004 |
161| Okinawa | ¥952 |
162 
163The government targets ¥1,500/hour by the late 2020s.
164 
165### Overtime (Labour Standards Act)
166 
167| Category | Premium Rate | Legal Basis |
168|---|---|---|
169| Regular overtime (> 8 hrs/day or > 40 hrs/week) | 125% (25% premium) | Art. 37(1) |
170| Overtime exceeding 60 hrs/month | 150% (50% premium) | Art. 37(1) proviso |
171| Late-night work (22:00--05:00) | 125% (25% premium) | Art. 37(4) |
172| Overtime + late-night | 150% (25% + 25%) | Combined |
173| Statutory holiday work (法定休日) | 135% (35% premium) | Art. 37(1) |
174| Statutory holiday + late-night | 160% (35% + 25%) | Combined |
175 
176### 36 Agreement (三六協定)
177 
178Overtime requires a written labour-management agreement (36 Agreement) filed with the Labour Standards Inspection Office. Limits:
179 
180| Limit | Standard | Special Clause |
181|---|---|---|
182| Monthly | 45 hours | Up to 100 hours (incl. holiday work) |
183| Annual | 360 hours | Up to 720 hours |
184| Multi-month average | -- | Must not exceed 80 hrs/month over any 2--6 month window |
185 
186Violations can result in penalties of up to ¥300,000 fine or 6 months imprisonment.
187 
188---
189 
190## Section 6 -- Mandatory Benefits
191 
192### Annual Paid Leave (年次有給休暇)
193 
194| Years of Service | Days Granted |
195|---|---|
196| 0.5 years | 10 days |
197| 1.5 years | 11 days |
198| 2.5 years | 12 days |
199| 3.5 years | 14 days |
200| 4.5 years | 16 days |
201| 5.5 years | 18 days |
202| 6.5+ years | 20 days (maximum) |
203 
204Requires 80% attendance in the preceding year. Employers must ensure employees take at least 5 days per year. Unused leave expires after 2 years.
205 
206### Maternity Leave (産前産後休業)
207 
208- Pre-birth: 6 weeks (14 weeks for multiple pregnancy)
209- Post-birth: 8 weeks (mandatory)
210- Benefit: approximately 67% of daily wage from health insurance (出産手当金)
211- Lump-sum birth allowance: ¥500,000 (出産育児一時金)
212 
213### Childcare Leave (育児休業)
214 
215Up to the child's first birthday (extendable to 2 years if daycare unavailable). Benefit: 67% of wage for first 180 days, then 50%, from employment insurance. Social insurance premiums are exempt during leave.
216 
217### Sick Leave
218 
219No statutory paid sick leave in Japan. Employers typically provide 3--10 days contractually. Health insurance provides injury/sickness allowance (傷病手当金) at 2/3 of daily wage from the 4th day of absence, for up to 18 months.
220 
221### Retirement Allowance (退職金)
222 
223Not legally required but deeply customary. Approximately 80% of large employers and 70% of SMEs offer some form of retirement benefit (lump sum, defined benefit, or defined contribution pension).
224 
225---
226 
227## Section 7 -- Payslip Requirements
228 
229Employers must provide a pay statement (給与明細書 kyūyo meisai-sho) each pay period under the Income Tax Act and Labour Standards Act.
230 
231### Mandatory Payslip Contents
232 
233- Employee name
234- Pay period and payment date
235- Base salary (基本給)
236- All allowances itemised (commuting 通勤手当, overtime 時間外手当, housing 住宅手当, etc.)
237- Gross pay
238- Deductions itemised:
239 - Health insurance premium
240 - Long-term care insurance premium (if applicable)
241 - Welfare pension premium
242 - Employment insurance premium
243 - Income tax withholding (所得税)
244 - Resident tax (住民税) -- withheld June through May
245- Net pay
246- Working hours and overtime hours
247 
248### Resident Tax (住民税)
249 
250Resident tax is calculated by the municipality based on prior-year income. The municipality sends the employer a notification in May with monthly withholding amounts for June through the following May (special collection / 特別徴収). This is a flat amount per month, not percentage-based.
251 
252---
253 
254## Section 8 -- Filing Obligations
255 
256### Monthly Withholding Tax Payment
257 
258| Employer Size | Due Date |
259|---|---|
260| Standard | 10th of the following month |
261| Small employer (≤ 10 employees, with approval) | Semi-annually: 10 July (Jan--Jun) and 10 January (Jul--Dec) |
262 
263Payment via bank transfer or e-Tax (国税電子申告 e-Tax).
264 
265### Year-End Adjustment (年末調整)
266 
267| Task | Deadline |
268|---|---|
269| Collect employee declarations (扶養控除等申告書, 保険料控除申告書, etc.) | November--December |
270| Perform year-end adjustment calculation | December payroll |
271| Issue withholding tax slip (源泉徴収票) to employees | 31 January |
272| File 法定調書合計表 (statutory report summary) to tax office | 31 January |
273| Submit 給与支払報告書 (salary payment report) to municipality | 31 January |
274 
275### Social Insurance Reporting
276 
277| Report | Deadline | Authority |
278|---|---|---|
279| 算定基届 (annual SMR determination) | 1--10 July | Japan Pension Service |
280| 月額変更届 (mid-year SMR change) | Promptly upon qualifying change | Japan Pension Service |
281| 賞与支払届 (bonus payment notification) | Within 5 days of bonus payment | Japan Pension Service |
282| 労働保険年度更新 (annual labour insurance update) | 1 June -- 10 July | Labour Bureau |
283 
284### Penalties
285 
286| Violation | Consequence |
287|---|---|
288| Late withholding tax payment | 5%--10% additional tax (不納付加算税) + delinquency tax (延滞税) |
289| Failure to withhold | Employer liable for full tax amount |
290| Overtime limit violation (36 Agreement) | Up to ¥300,000 fine or 6 months imprisonment |
291| Failure to grant minimum 5 days paid leave | Up to ¥300,000 fine per violation |
292| Failure to enrol in social insurance | Up to 6 months imprisonment or ¥500,000 fine; retroactive enrolment + premiums |
293 
294---
295 
296## Section 9 -- Common Payroll Patterns
297 
298### Pattern 1 -- Standard Monthly Employee (Tokyo, Age 35)
299 
300Monthly salary ¥350,000. No dependents (甲 column, 0 dependents). Commuting allowance ¥15,000/month (non-taxable up to ¥150,000/month).
301 
3021. Health insurance: ¥350,000 × 4.925% = ¥17,238
3032. Welfare pension: ¥350,000 × 9.15% = ¥32,025
3043. Employment insurance: ¥365,000 × 0.50% = ¥1,825 (on total wages incl. commuting)
3054. Child-rearing support: ¥350,000 × 0.115% = ¥403
3065. Income tax: per monthly table 甲, 0 dependents, ¥350,000 minus social insurance = ~¥8,250
3076. Resident tax: per municipality notification (e.g., ¥18,000/month)
3087. Net pay: ¥350,000 + ¥15,000 - deductions ≈ ¥287,259
309 
310Employer additionally pays: ¥17,238 (health) + ¥32,025 (pension) + ¥1,260 (child allowance) + ¥403 (child-rearing) + ¥3,103 (employment ins.) + ¥1,095 (workers' comp) = ~¥55,124
311 
312### Pattern 2 -- Bonus Payment (Summer/Winter)
313 
314Employee with SMR grade ¥350,000 receives ¥700,000 summer bonus.
315 
3161. Health insurance: ¥700,000 × 4.925% = ¥34,475
3172. Welfare pension: ¥700,000 × 9.15% = ¥64,050 (under ¥1,500,000 per-bonus cap)
3183. Employment insurance: ¥700,000 × 0.50% = ¥3,500
3194. Income tax: per bonus withholding table (賞与に対する源泉徴収税額の算出率の表) -- rate based on prior month's social-insurance-deducted salary
3205. No resident tax on bonus (already covered by monthly flat amount)
321 
322### Pattern 3 -- Mid-Year Salary Change (随時改定)
323 
324Employee's base salary increases from ¥300,000 to ¥350,000 in April. If the new SMR grade is 2+ grades different from the current grade, the employer files a 月額変更届. New SMR takes effect from July. Social insurance premiums update from the July payroll.
325 
326### Pattern 4 -- Employee on Childcare Leave
327 
328Social insurance premiums (both employee and employer shares) are exempt during childcare leave. Employment insurance premiums are not charged on zero-pay months. The employee receives childcare leave benefits from employment insurance (67% for first 180 days, 50% thereafter).
329 
330---
331 
332## Section 10 -- Interaction with Other Skills
333 
334| Skill | Interaction |
335|---|---|
336| payroll-workflow-base | Provides generic payroll processing steps; this skill adds Japan-specific rules |
337| japan-bookkeeping | Payroll journals: salaries + ER social insurance to P&L; net pay + withholding tax + social insurance payable to BS |
338| japan-consumption-tax | No consumption tax on salaries; commuting allowances are non-taxable for income tax but included in employment insurance base |
339| japan-corporate-tax | Employer social insurance contributions and retirement allowance provisions are deductible expenses |
340 
341---
342 
343## Disclaimer
344 
345This skill and its outputs are provided for informational and computational purposes only and do not constitute tax, legal, or financial advice. Open Accountants and its contributors accept no liability for any errors, omissions, or outcomes arising from the use of this skill. All outputs must be reviewed and signed off by a qualified professional (such as a CPA, EA, tax attorney, or equivalent licensed practitioner in your jurisdiction) before filing or acting upon.
346 
347The most up-to-date, verified version of this skill is maintained at [openaccountants.com](https://openaccountants.com). Log in to access the latest version, request a professional review from a licensed accountant, and track updates as tax law changes.
348 

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About

Use this skill whenever asked about Japanese payroll, income tax withholding (源泉徴収 gensen chōshū), social insurance (社会保険 shakai hoken), labour insurance (労働保険 rōdō hoken), or employer obligations in Japan. Trigger on phrases like "gensen choshu", "源泉徴収", "shakai hoken", "社会保険", "厚生年金", "kosei nenkin", "kenko hoken", "健康保険", "雇用保険", "koyou hoken", "労災保険", "rosai hoken", "年末調整", "nenmatsu chousei", "year-end adjustment", "standard monthly remuneration", "hyōjun hōshū getsugaku", "payslip Japan", "給与明細", "kyūyo meisai", "minimum wage Japan", "overtime Japan", "36 agreement", "子ども・子育て支援金", or any question about running payroll in Japan. ALWAYS read this skill before processing any Japanese payroll work.

JPty-2025

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