Base de cotización (social security contribution base)

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.

In practice, when you register with RETA you pick your bracket based on the net income you expect, and within the bracket you pick the base. A higher base makes the quota more expensive but improves benefits; the minimum base lowers the monthly cost, but leaves smaller benefits if you ever need them.

The typical mistake is choosing the minimum base of the lowest bracket «to pay little» without reviewing your forecast. If you end up earning more, the regularización de cuotas will ask for the difference in one go the following year. The other way round, overestimating means you advance money that is later refunded.

It is linked to RETA, the regularización de cuotas, pluriactividad and cese de actividad. The quota is a deductible expense of an autónomo's activity, and kontora records it in your books every month.

Guides that use this term

• The autónomo quota increase in 2026: how much it really rises, bracket by bracket

Related terms

• Autónomo: An autónomo is a self-employed individual who works independently in Spain and bears the financial risk of their own business.
• RETA: RETA is the special social security scheme that self-employed workers, including corporate autónomos, contribute to in Spain.
• Regularización de cuotas: The regularización de cuotas is the annual RETA true-up: the following year, social security compares the contributions you paid against your real net income as reported by the tax agency.
• Pluriactividad: Pluriactividad means being an employee and self-employed at the same time, contributing simultaneously to the general regime and to RETA (the self-employed scheme).
• Cese de actividad: Cese de actividad is the benefit covering self-employed workers forced to shut down, roughly the unemployment benefit for autónomos.

Full glossary