How Much Tax Does a French Employee in Korea Pay at 50M / 100M / 200M KRW?
(Normal progressive tax vs 19% flat tax, with example numbers)
Imagine a French professional from Paris, Pierre, working in Korea for a full year.
He hears that Korea offers two different tax options for foreign workers:
The normal Korean progressive tax system (same structure as Koreans), and
A special 19% flat tax regime for foreign employees.
The natural questions are:
“At 50M, 100M, or 200M KRW of salary, how much do I actually take home?”
“Is the 19% flat rate always better than the progressive system?”
Below is a simplified, numeric comparison you can use to understand the trade‑offs.
Important assumptions (for illustration only)
Pierre is tax resident in Korea (lives and works in Korea the whole year).
He has employment income only, from a Korean employer.
He is single (only his own basic deduction applies).
No tax‑free allowances or fringe benefits are assumed.
No extra deductions/credits are assumed (no pension savings, medical, education, card deductions, donations, etc.).
Korean social insurance employee shares are applied as a flat percentage of salary (caps are ignored for simplicity):
National Pension: 4.75%
Health Insurance: 3.595%
Long‑term Care: 13.14% of the health premium
Employment Insurance: 0.9%
In real life, caps, exemptions, and extra deductions can change the numbers, but this model shows the direction and magnitude quite clearly.
1. Two tax options Pierre can choose
Option 1 – Normal Korean progressive tax (resident, same structure as Koreans)
As a Korean tax resident, Pierre is taxed like any other resident employee. In simple terms:
Start with gross salary.
Subtract the earned income deduction (a standard deduction based on salary).
Subtract the basic personal deduction for himself.
Apply the progressive income tax rates (6–45%) to the taxable base and compute national tax.
Apply the earned income tax credit (a credit only for salary income, subject to limits).
Add local income tax, which is 10% of the final national income tax.
Because of the deductions and the tax credit, the effective tax rate can be significantly lower than the top marginal rates, especially at low and middle income levels.
Option 2 – 19% flat tax regime for foreign workers
Pierre can instead elect a special regime for foreign employees:
Apply 19% national income tax to his Korean employment income,
Add local income tax equal to 10% of that national tax.
This is effectively about 20.9% of the chosen tax base (19% + 1.9%).
This flat rate can generally be used for up to 20 years, starting from the year he begins working in Korea, if conditions are met.
But electing the flat tax comes with a major catch: Pierre usually gives up the benefit of the normal deductions, exemptions, tax‑free items, and tax credits he would otherwise enjoy under the progressive system.
2. Example numbers: 50M / 100M / 200M KRW
Below, all social insurance contributions are employee shares only, based on the simplified rates above.
2.1 Salary: 50,000,000 KRW
Normal progressive system
Gross salary: 50,000,000 KRW
Earned income deduction: 12,250,000 KRW
Earned income (after deduction): 37,750,000 KRW
Basic personal deduction (Pierre): 1,500,000 KRW
Tax base (taxable income): 36,250,000 KRW
Income tax:
National income tax (after credit): 3,517,500 KRW
Local income tax (10%): 351,750 KRW
Total income tax: 3,869,250 KRW
Employee social insurance (approx.):
National Pension (4.75%): 2,375,000 KRW
Health Insurance (3.595%): 1,797,500 KRW
Long‑term Care: ≈ 236,000 KRW
Employment Insurance (0.9%): 450,000 KRW
Total social insurance: ≈ 4,858,700 KRW
Result:
Total deductions (tax + social insurance): ≈ 8,728,000 KRW
Net salary: ≈ 41,272,000 KRW (about 82.5% of gross)
19% flat tax regime
Assume the full 50,000,000 KRW is the flat‑tax base (no deductions, no tax‑free income):
National income tax (19%): 9,500,000 KRW
Local income tax (1.9%): 950,000 KRW
Total income tax: 10,450,000 KRW
Social insurance (same as above): ≈ 4,858,700 KRW
Result:
Total deductions: ≈ 15,309,000 KRW
Net salary: ≈ 34,691,000 KRW (about 69.4% of gross)
Comparison at 50M KRW
Normal system net: ~41.3M KRW
Flat tax net: ~34.7M KRW
→ At 50M, the flat regime costs Pierre over 6M KRW more per year in total deductions.
2.2 Salary: 100,000,000 KRW
Normal progressive system
Gross salary: 100,000,000 KRW
Earned income deduction: 14,750,000 KRW
Earned income: 85,250,000 KRW
Basic deduction: 1,500,000 KRW
Tax base: 83,750,000 KRW
Income tax:
National income tax (after credit): 13,840,000 KRW
Local income tax: 1,384,000 KRW
Total income tax: 15,224,000 KRW
Social insurance (approx.):
National Pension: 4,750,000 KRW
Health Insurance: 3,595,000 KRW
Long‑term Care: ≈ 472,000 KRW
Employment Insurance: 900,000 KRW
Total social insurance: ≈ 9,717,000 KRW
Result:
Total deductions: ≈ 24,941,000 KRW
Net salary: ≈ 75,059,000 KRW (about 75.1% of gross)
19% flat tax regime
National income tax (19% of 100M): 19,000,000 KRW
Local income tax (1.9%): 1,900,000 KRW
Total income tax: 20,900,000 KRW
Social insurance: same ≈ 9,717,000 KRW
Result:
Total deductions: ≈ 30,617,000 KRW
Net salary: ≈ 69,383,000 KRW (about 69.4% of gross)
Comparison at 100M KRW
Normal system net: ~75.1M KRW
Flat tax net: ~69.4M KRW
→ At 100M, the flat regime still reduces Pierre’s net pay by around 5–6M KRW in this simple model.
2.3 Salary: 200,000,000 KRW
Normal progressive system
Gross salary: 200,000,000 KRW
Earned income deduction: 16,750,000 KRW
Earned income: 183,250,000 KRW
Basic deduction: 1,500,000 KRW
Tax base: 181,750,000 KRW
Income tax:
National income tax (after credit): 48,925,000 KRW
Local income tax: 4,892,500 KRW
Total income tax: 53,817,500 KRW
Social insurance (approx.):
National Pension: 9,500,000 KRW
Health Insurance: 7,190,000 KRW
Long‑term Care: ≈ 945,000 KRW
Employment Insurance: 1,800,000 KRW
Total social insurance: ≈ 19,435,000 KRW
Result:
Total deductions: ≈ 73,252,000 KRW
Net salary: ≈ 126,748,000 KRW (about 63.4% of gross)
19% flat tax regime
National income tax (19% of 200M): 38,000,000 KRW
Local income tax (1.9%): 3,800,000 KRW
Total income tax: 41,800,000 KRW
Social insurance: same ≈ 19,435,000 KRW
Result:
Total deductions: ≈ 61,235,000 KRW
Net salary: ≈ 138,765,000 KRW (about 69.4% of gross)
Comparison at 200M KRW
Normal system net: ~126.7M KRW
Flat tax net: ~138.8M KRW
→ At 200M, the flat tax now wins, leaving Pierre with about 12M KRW more net pay than the normal progressive system in this example.
3. What this means for a French employee from Paris
In this simplified scenario:
At 50M and 100M KRW, the normal Korean progressive system produces a higher net salary than the 19% flat tax.
At 200M KRW, the 19% flat tax starts to outperform the normal system in terms of take‑home pay.
The underlying logic is:
At lower incomes, deductions and the earned income tax credit make the normal system quite efficient.
At high incomes, the progressive rates push the effective burden up, and a flat rate around 20.9% on a broader base can become the cheaper option.
In practice, a real French employee in Korea also has to consider:
Spouse/dependents and personal deduction eligibility,
Non‑taxable allowances and employer‑provided benefits,
Extra deductions and credits,
Social insurance caps,
And French tax rules plus the France–Korea tax treaty.
So the safest rule of thumb is:
Never choose the 19% flat tax blindly.
Always run both scenarios—normal progressive vs flat—using real payroll and deduction data,
then pick the one that gives the higher net income
