SZČO calculator 2026
Sole trader · net income per year · health insurance settlement · contribution forecast
Health insurance under / overpayment · annual settlement
Contribution forecast for next year
Calculation detail
How the SZČO calculator works
The calculator computes a sole trader's (SZČO) yearly figures from annual income: income tax, the contributions actually applied, net yearly income, the annual health insurance settlement (underpayment or refund) and a forecast of the new social and health insurance advances for the next year. It supports 60 % flat-rate expenses as well as actual expenses, ZŤP status and a deferred tax return.
Parameters for 2026
- Income tax of 15 % on taxable income up to 100,000 € per year; above that, the tax base falls into the 19/25/30/35 % bands (Act No. 595/2003 Coll.).
- Personal tax allowance: 21 times the subsistence minimum of 284.13 €; it tapers off at higher tax bases.
- Flat-rate expenses: 60 % of income, at most 20,000 € per year, plus paid contributions. The flat rate is not available to a VAT payer who held that status for the entire year.
- Sole trader social insurance: a 33.15 % rate on the assessment base; minimum advance of 303.11 € per month (minimum base 914.40 €), maximum 5,557.26 €.
- From 1 July 2026 a three-tier social insurance income test applies: with income up to 10.5 times the 2024 subsistence minimum (2,876.90 €) no social insurance is paid; up to 9,144.01 € (50 % of the average assessment base) a micro-contribution of 131.34 € per month applies; above that, the standard calculation.
- Sole trader health insurance: 16 % of the assessment base (8 % with ZŤP); minimum advance of 121.92 € per month (60.96 € with ZŤP).
How the calculation runs
- Expenses: the 60 % flat rate (max 20,000 €) plus paid contributions, or actual expenses including contributions.
- The tax base is reduced by the tax allowance; tax is computed at 15 % or across the bands and rounded under § 47 of Act No. 595/2003 Coll.
- Annual health insurance settlement: the real premium of 16 % of the assessment base is compared with the advances paid — the result is an underpayment (payable to the insurer) or an overpayment (the insurer refunds it). Social insurance has no settlement; its advances are final.
- Forecast for the next year: the new social insurance advance applies from 1 July (from 1 October with a deferred return), the new health insurance advance from 1 January.
If you leave the paid advances empty, the calculator estimates them from the registration date (month and year) and the minimum advances of the respective year.
Frequently asked questions
When do flat-rate expenses pay off versus actual expenses?
The calculator shows both figures side by side: deductible expenses under the flat rate (60 % plus contributions) and under actual expenses. Which regime works out better depends on the share of real costs in income — the result is visible directly in the calculation. A VAT payer for the whole year cannot use the flat rate.
What is the health insurance underpayment?
The advances a sole trader pays during the year are only a prepayment. After the tax return is filed, the health insurer runs the annual settlement: if the real premium (16 % of the assessment base) exceeds the advances paid, an underpayment arises; if it is lower, the insurer refunds the difference.
From when do the new advances apply after filing?
Social insurance changes from 1 July; if the return was deferred until 30 June, from 1 October. Health insurance advances for the new year apply from 1 January. The calculator shows the change date right in the forecast.