Taxes & income tax
How to adjust your social security contribution base
October is the month to submit your quarterly social security declaration. Did you know the law allows you to adjust your contribution base to better manage your cash flow?
What is the contribution base
The contribution base is the amount upon which your social security contribution rate is applied. This value is calculated based on the income you report quarterly, applying coefficients of 70% for service provision or 20% for the sale of goods.
The flexibility of the adjustment
The law allows you to adjust your contribution base within a range of 5% to 25% upwards or downwards from the automatically calculated value. This is a powerful tool for those with irregular income.
Steps to submit the declaration
- Access the Direct Social Security portal.
- Select the option Work, Remuneration and contributions.
- Choose Independent Workers and then Submit quarterly declaration.
- Confirm the income invoiced between July and September.
- Apply the 5% to 25% adjustment if necessary and submit.
Remember that the October quarterly declaration sets the contributions you will pay in the months of November, December, and January 2027.
Official sources
This article is for information only and does not replace personalized tax or accounting advice. Rates, limits, and rules can change. Always check your situation with a certified accountant or the official bodies listed above.
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