How social contributions are calculated

As a self-employed person, you must pay social contributions to your social insurance fund. In return, you receive some social rights and benefits (legal pension, healthcare, child allowance, bridging rights, etc.) But how are social contributions calculated? On what criteria is the calculation based? We explain it all here. 

The formula for calculating social contributions 

To calculate social contributions, we take your gross income (including your company car and other benefits of any kind). We then subtract certain items from this: 

  • business expenses (flat-rate or real), operating costs and possible losses 

  • any social security contributions you have already paid 

  • the contributions you pay for your Private Supplementary Pension for the Self-Employed (PSPSE). 



Don’t forget other factors also affect your gross income. Your accountant can give you more information on this. 

How much social contributions do you have to pay?

Starting self-employed (< 3 years in business)


During your first 3 calendar years of self-employment, you can pay flat-rate (minimum) contributions. 

'Established' self-employed (> 3 years in business)


If you have been self-employed for more than 3 years, you belong to the "definitive regime". Your social contributions then represent a percentage of your net taxable income, determined according to the income scales. 


The social contributions you pay are always provisional contributions 

As a self-employed person, you must pay social contributions every quarter. These contributions are always provisional, as they are calculated based on your expected income

The reason for this is that we, as your social insurance fund, must calculate and collect your contributions for the current year, when your actual income is not yet known. As soon as your actual income is known, we will make a final calculation. 

Have you earned more than expected and therefore paid too few contributions? Then you must pay an allowance. Have you earned less than expected and therefore paid too many contributions? Then we will refund you the difference

Is the difference between your contributions and your actual income very large? Then it pays to optimise your contributions. 

If you start out as self-employed, you can pay a flat-rate contribution for the first 3 years. This is because we only receive your actual income from the tax authorities after 2 or 3 years. Only from then on can we make a final calculation of your contributions. 


Join our social insurance fund

Looking for a social insurance fund that understands your concerns as a self-employed person? Join Partena Professional and make it easy on yourself.