Methodology for the Belgian self-employed net income calculation

1. From turnover to net professional income

Turnover excluding VAT is obtained by multiplying the daily rate by the number of actually billable days. VAT is neutral on net income: it is collected then remitted to the State.

Professional expenses (capped legal lump sum, or justified actual costs) are deducted from turnover to obtain the net taxable professional income.

2. INASTI social contributions

Social contributions are computed on the net professional income, at the ordinary rate of about 20.5% on the first bracket, then a reduced rate on a higher bracket, and nil above a cap. A minimum and a maximum quarterly contribution apply.

The activity category (main, secondary, primostarter, assisting spouse) changes the minima/maxima and the exemption threshold. The social insurance fund's management fee (free, ~4%) is added to the legal contribution and shown separately.

3. Taxable income and deductions

The social contributions paid and the voluntary supplementary pension premium (VAPZ/PLCI, deductible within a percentage of net income and an absolute cap) reduce the taxable income.

Private hospitalization insurance is generally not deductible for the natural person: it is shown for information only.

4. Personal income tax

The taxable income is subject to the progressive income tax schedule, increased by the average communal surcharges. The tax-exempt quota, its supplements for dependent children and persons, and the marital quotient (schedule II for the spouse without income) are applied.

Net income = net professional income − total social contributions − income tax. The overall pressure rate measures the gap between turnover and net.

5. Legal sources

Self-employed status: Royal Decree no. 38 of 27 July 1967 organizing the social status of the self-employed.

Personal income tax: Income Tax Code 1992 (CIR 92).

Yearly indexation: INASTI and SPF Finances schedules published annually. No value is approximated: the calculation refuses to produce a result until the official schedules are loaded.