Enter what you invoiced over the three months of the quarter (the figure from the quarterly declaration). The monthly base is 1/3 of the relevant income and you can adjust it by ±25%. In the first year of activity there is generally an exemption for the first 12 months.
| Item | Amount |
|---|---|
| Relevant income (quarter) | €5,250.00 |
| Monthly contribution base | €1,750.00 |
| Monthly contribution | €374.50 |
| Quarterly contribution | €1,123.50 |
Estimates the Social Security contribution of a self-employed worker. It does not include IRS (Category B), VAT (IVA), or the exemption when combining with employed work.
Educational estimate, not tax advice. The 21.4% rate (25.2% for sole traders), the 70%/20% coefficients, the €20 minimum and the 12 × IAS ceiling are official for 2026. Check on Segurança Social Direta.
Self-Employed Social Security Calculator (Portugal) by Calculadora Capital