Comprehensive Income Tax Estimator
Estimates 종합소득세 from business, salary and other income with 인적공제, pension deduction, 자녀·표준세액공제 and 지방소득세, showing every step; expense ratios and itemised credits are entered, not looked up.
The May 종합소득세 filing brings business, salary and other income together, applies 인적공제 and credits, and taxes the result at the 소득세법 §55 (Income Tax Act, art. 55) progressive rates plus 지방소득세 at 10% of the tax. This works through those steps and shows each one, so you can see where the number comes from before it appears on a 신고서.
Calculated on the 2026 rates.
2026년 기준 · 소득세법 §55 (Income Tax Act, art. 55) basic rates, 6–45% · 지방소득세 10% of the tax
For 종합소득세 (comprehensive income tax) on 2026 income, filed the following May. The 소득세법 (Income Tax Act) text is the version confirmed at 법제처 on 2026-09-02 (in force from 1 January 2026), and this table is valid until 2026-12-31.
The employer-side contributions (고용안정·직업능력개발, 산재보험) vary with headcount and industry, so an average is used here. Your actual invoice will differ.
Rates change every year. If this still reads 2026 after 2026 has passed, the figures are out of date.
Income
Turnover. For a freelancer, the figure before the 3.3% is withheld
Expenses from the books, or computed from an expense ratio
Excluding non-taxable pay. Zero if none
Income from interest, dividends, pension and other income
Business income is revenue less allowable expenses. Without books, enter the expenses computed from the 단순경비율 or 기준경비율 that 홈택스 gave you — the per-industry expense-ratio tables are not here.
Deductions
1,500,000 each. A spouse or dependant with income of 1,000,000 or less qualifies
경로우대: 1,000,000 each
2,000,000 each
자녀세액공제: 250,000 for one, 550,000 for two, 400,000 for each after that
Your own 국민연금 contributions, fully deductible
노란우산, housing funds and the like, after their own caps
Pension accounts, medical, education, donations, statutory reliefs
For 3.3% withholding, the 3% part of it (total × 3 ÷ 3.3)
Tax
Income tax payable
2,045,000원
Truncated below ten won
결정세액 — tax determined
3,845,000원
지방소득세 — local income tax
384,500원
Filed and paid separately (10% of the determined tax)
Total tax
4,229,500원
Income tax plus local income tax
Effective rate
11.75%
Against comprehensive income
| Step | Amount | Basis |
|---|---|---|
| +사업소득 수입금액 — business turnover | 60,000,000원 | |
| −필요경비 — allowable expenses | 24,000,000원 | |
| =종합소득금액 — total aggregate income | 36,000,000원 | |
| −인적공제 — personal deduction (기본공제 for 1 person) | 1,500,000원 | 소득세법 §§50, 51 |
| =과세표준 — tax base | 34,500,000원 | |
| =산출세액 — computed tax (at 15%, less the progressive deduction) | 3,915,000원 | 소득세법 §55 |
| −표준세액공제 — standard tax credit | 70,000원 | 소득세법 §59-4(9) |
| =결정세액 — tax determined | 3,845,000원 | |
| +지방소득세 — local income tax, 10% of the tax determined | 384,500원 | 지방세법 §92 (Local Tax Act) |
| −기납부세액 — tax already paid (the 소득세 part) | 1,800,000원 |
What this calculator does not model
- Deemed expenses under the 단순경비율 or 기준경비율 — those need the per-industry expense-ratio tables, so expenses are entered by you.
- Whether 성실신고확인 applies and the deductions and penalties that follow from it.
- Capped income deductions such as 노란우산, pension savings and housing funds — enter the total in “other income deductions”.
- Itemised 특별세액공제 for medical, education, donations and rent — where those are claimed instead of the standard credit, enter them in “other tax credits”.
- Reliefs under the 조세특례제한법, such as the small-business tax reduction, and 농어촌특별세.
- Separately taxed and non-taxable income, the 20,000,000 threshold for aggregating financial income, and the separate-taxation election for rental income.
- Penalties for non-filing or late payment, and paying in instalments.
How to use it
Enter each kind of income separately
Business, salary and other income are treated differently before they are summed — salary gets 근로소득공제, business income is gross less expenses.
Enter your expenses, not a ratio the tool guessed
The 단순경비율 and 기준경비율 tables are published per business code and change annually; this tool does not carry them. Enter the expense figure you will actually declare.
Set 인적공제 and dependants
기본공제 per qualifying person plus the 추가공제 categories — 경로우대, 장애인, 부녀자 (subject to an income cap), 한부모 — under 소득세법 §§50–51 (arts. 50–51). Where 부녀자 and 한부모 overlap, only the latter applies.
Subtract the tax already withheld
The 3.3% withheld from freelance income through the year is an advance payment. The figure that matters is the tax computed here minus what has already been paid — often a refund.
Common questions
Which law and which effective date?
The 소득세법 as in force for the current tax year, read from the statute text served by 법제처 국가법령정보센터 on the date recorded in the rate module: the §55 brackets, the §§50–51 personal deductions, the §59-2 child credit as amended for 2025, and the §59-4(9) standard credit. The page carries the year and a validity date, and a test fails once that date passes.
What does it not model?
The 경비율 tables, every itemised 특별세액공제 (의료비, 교육비, 기부금, 주택자금), 세액감면, 가산세, and the 성실사업자 variant of the standard credit. Those are entered by you or left out entirely, so the result is an estimate that will differ from a completed return.
Can I file with this figure?
No. It is an estimate for planning — knowing roughly what to set aside before May. A filing is made at 홈택스 against your actual 지급명세서 and receipts, and the deductions this tool leaves to you are exactly the ones that move the result most.
Why is 지방소득세 10% but so small?
Because it is 10% of the income tax, not of the income. On a tax of 2,000,000 won it is 200,000 won, and it is filed and paid separately from the national tax.
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