Flat Tax Calculator

Fixed rate of 19% for sole proprietorship. 2026 rates.

Input data — monthly

0 zł50,000 zł100,000 zł
0 zł25,000 zł50,000 zł

Results — monthly

Net income (take-home)
Revenue
Tax-deductible costs
Income (revenue − costs)
ZUS social contributions
Health insurance contribution (4.9%)
PIT tax advance (19%)
Effective burden rate

Results — yearly

Yearly net income
Yearly PIT tax
Yearly ZUS + health insurance

Flat Tax 2026 — key rules

PIT rate

  • 19% — fixed rate regardless of income
  • No tax-free amount
  • No joint filing with spouse

Health insurance contribution

  • 4.9% of income
  • Minimum: 432.54 zł (9% × 4,806 zł)
  • Deductible from income up to 14,100 zł per year

When is it beneficial?

  • Income above ~120,000 zł per year
  • Lower health insurance contribution (4.9% vs 9%)
  • Fixed rate provides predictability

Flat Tax — what you should know

Health insurance deduction

Entrepreneurs on flat tax can deduct paid health insurance contributions from income, but only up to a limit of 14,100 zł per year (in 2026). For income above approximately 290,000 zł per year, the limit does not cover the full contribution. This is a significant change introduced by the Polish Deal (Polski Ład).

Comparison with lump-sum tax

With low tax-deductible costs, lump-sum tax (e.g., 12% for IT) may be more beneficial than flat tax. Lump-sum tax also offers lower health insurance contributions in three fixed tiers. However, lump-sum tax does not allow deducting income-earning costs — the choice depends on the structure of revenues and costs.

Loss of flat tax eligibility

An entrepreneur loses the right to flat tax if they provide services to a former employer in the same scope as their previous employment — in the year of transitioning to B2B. This restriction applies to the first tax year after changing the form of employment.