Base de cotización (social security contribution base)

The base de cotización is the amount on which social security percentages are applied to calculate what you pay into the system. Employees have it tied to their salary, while the self-employed choose it within the bracket matching their forecast net income.

In 2026 there are 15 income brackets, frozen at 2025 levels: within each one you pick a base between the bracket's minimum and maximum (with an overall cap of 5,101.20 euros), and you can change it up to 6 times a year as your forecast changes. Your base determines both your monthly quota (31.5% of the base) and your future benefits: sick leave, cessation of activity, and pension. The official simulator is Import@ss.

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Modelo 720 (foreign assets declaration)

Regularización de cuotas (annual adjustment of self-employed contributions)

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