Comprehensive Income Tax Calculator
Enter revenue and expenses to instantly see whether you get a refund or owe additional tax. Includes 3.3% freelancer withholding settlement.
Income Information
Default 70,000 KRW is the standard tax credit (for comprehensive income earners who do not file special tax credits — Income Tax Act Art. 59-4(9)).
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Additional Tax Due
2025-2026 common tax rate table (Income Tax Act Art. 55, current) applied — Sources- Gross Revenue
- 40,000,000 KRW
- Necessary Expenses
- -0 KRW
- Comprehensive Income
- 40,000,000 KRW
- Income Deductions
- −1,500,000 KRW
- Tax Base
- 38,500,000 KRW
- Tax Rate / Progressive Deduction
- 15% · 1,260,000 KRW
- Calculated Tax
- 4,515,000 KRW
- Tax Credits
- −70,000 KRW
- Determined Tax
- 4,445,000 KRW
- Local Income Tax
- 444,500 KRW
- Total Tax Liability
- 4,889,500 KRW
- Prepaid Tax3.3% of gross revenue
- 1,320,000 KRW
| Tax Base | Rate | Progressive Deduction |
|---|---|---|
| 1,400만원 or less | 6% | 0 KRW |
| Over 1,400만원 to 5,000만원 | 15% | 1,260,000 KRW |
| Over 5,000만원 to 8,800만원 | 24% | 5,760,000 KRW |
| Over 8,800만원 to 15,000만원 | 35% | 15,440,000 KRW |
| Over 15,000만원 to 30,000만원 | 38% | 19,940,000 KRW |
| Over 30,000만원 to 50,000만원 | 40% | 25,940,000 KRW |
| Over 50,000만원 to 100,000만원 | 42% | 35,940,000 KRW |
| Over 100,000만원 | 45% | 65,940,000 KRW |
This is a simplified calculation assuming only business income (including 3.3%-withheld freelance income). The following are not included.
- No built-in industry expense rate table. Thousands of industry codes are re-announced annually by the NTS. Enter expenses directly or look up your rate on Hometax.
- No income aggregation with employment, pension, interest, dividend, or other income. If you have multiple types, actual tax will be higher.
- Additional personal exemptions (senior, disabled, single parent), special tax credits (medical, education, donations), and pension/child credits are not auto-applied. Add them to 'Other deductions' and 'Tax credits' if applicable.
- National Pension, health insurance, Noran Usan (노란우산공제) are deductible but not auto-included.
- Penalties, reductions, installments, and loss carryforward are not calculated.
- If expenses exceed revenue, they are capped at revenue (no deficit handling).
Comprehensive income tax is filed May 1-31 each year. For exact amounts, use the NTS Hometax filing system or consult a tax professional.
Moneyple's Comprehensive Income Tax Calculator computes progressive tax rates (6–45%) for freelancers and sole proprietors.
What This Number Means
Freelancers can see their actual tax burden on 3.3%-withheld income. After subtracting expenses and basic deductions, the 8-bracket progressive rate determines the calculated tax.
3 Common Mistakes People Make Here
- Thinking 3.3% is the final tax — it is a prepayment, settled during the May filing.
- Forgetting necessary expenses — recognized business costs reduce the tax base.
- Believing low income means no filing is needed — file to get a refund when withholding exceeds confirmed tax.
Freelancer 3.3% is not the final tax — it is a prepayment. The actual tax is determined in the May comprehensive income tax filing.
머니플(Moneyple) · Formulas and rates verified by humans; commentary drafted with AI assistance and reviewed by the operator
How is comprehensive income tax (종합소득세) calculated?
Subtract expenses and deductions from earnings, then apply progressive tax rates to the remainder (tax base, 과세표준). Rates range from 6% to 45% across 8 brackets (Income Tax Act Art. 55). Higher rates apply only to the excess above each threshold. The 'rate minus progressive deduction' formula simplifies this.
Comprehensive income = Gross revenue − Necessary expenses
Tax base = Comprehensive income − Deductions (basic 1,500,000 KRW/person, etc.)
Calculated tax = Tax base × Rate − Progressive deduction
Total tax = (Calculated tax − Credits) + Local income tax (10% of income tax)
Settlement = Total tax − Prepaid tax (3.3% withholding, etc.)
Example — A freelancer earns 40M KRW with 25M KRW in expenses: comprehensive income is 15,000,000 KRW. Subtracting basic deduction 1,500,000 KRW → tax base 13,500,000 KRW (6% bracket). Calculated tax 810,000 KRW minus 70,000 KRW standard credit → determined tax 740,000 KRW, plus local tax 74,000 KRW = total 814,000 KRW. Since 3.3% prepaid is 1,320,000 KRW, 506,000 KRW is refunded.
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Why do freelancers recalculate the 3.3% in May?
Because 3.3% is a flat prepayment on gross revenue. Actual tax is determined only after subtracting expenses and deductions, so the two amounts almost always differ. The May filing (종합소득세 신고) reconciles this difference.
- Refund cases — Modest income with sufficient expenses/deductions. If tax base is 0, the entire 3.3% is refunded.
- Additional payment cases — High income where progressive rates exceed 3.3%, or when other income is aggregated.
- Checking prepaid tax — Auto-retrieved via payment statements on Hometax. The 3.3% checkbox estimates that amount from gross revenue.
- Standard credit: 70,000 KRW — For comprehensive income earners without employment income who don't file special credits (Art. 59-4(9)). Honest business operators: 120,000 KRW; employees: 130,000 KRW.
Missing the deadline incurs a 20% non-filing penalty plus late payment penalties. Even refund-eligible filers lose their refund without filing — check in May if you've ever had 3.3% withheld.
Frequently Asked Questions
Q. Does 3.3% withholding mean all tax is paid?
No. 3.3% is a prepayment (원천징수), not the final tax. It combines 3% income tax (Art. 129(1)(3)) and 0.3% local income tax (10% of income tax). Actual tax is recalculated in the May filing with expenses and deductions. If confirmed tax is less than 3.3% paid, the difference is refunded; if more, you pay the balance. Freelancers with modest income often receive refunds.
Q. When and who files comprehensive income tax?
Filing runs May 1–31 (June 30 for verified filers). Anyone with business, employment, interest, dividend, pension, or other income must file. Employees who completed year-end settlement (연말정산) need not file separately — but even small freelance income with 3.3% withholding requires combined filing. Non-filing incurs penalties and forfeits refunds.
Q. How are necessary expenses (필요경비) calculated?
Two methods: actual expenses with receipts (bookkeeping), or NTS-published industry expense rates (estimation). Without books, simple or standard expense rates apply by industry code. Since codes number in the thousands and are re-announced annually, this calculator has no built-in table. Look up your code on Hometax (Inquiry > Expense Rate) and use 'Calculate by rate (%)', or enter actual expenses directly.
Q. How do I get the 3.3% refunded?
File comprehensive income tax in May. Hometax auto-retrieves withheld amounts. After applying expenses and deductions, the confirmed tax is compared with prepaid tax. Example: 40M KRW revenue, 25M KRW expenses, 1 person deduction, 70,000 KRW credit → tax base 13,500,000 KRW, total tax 814,000 KRW. Prepaid 3.3% is 1,320,000 KRW, so 506,000 KRW is refunded, typically deposited late June to early July.
This calculator is for reference only. Actual tax varies by income type, industry, deductions, and legal amendments. For exact amounts, use the NTS Hometax filing system or consult a tax professional.