Spanish Freelancer Social Security Calculator 2026

How the bracket-based contribution system works

Since 2023 the self-employed contribution is no longer freely chosen but depends on the net income you expect to earn. The system defines fifteen income brackets, each with an associated minimum contribution base. The procedure is as follows: you calculate your expected monthly net income, find the bracket it falls into, and apply the general contribution rate — around 31.4% — to that bracket's minimum base. You may choose to contribute on a base higher than your bracket's minimum if you want to improve your future benefits, but never below it.

Worked example

Take a self-employed worker who invoices €2,500 a month and has €400 of deductible expenses. Their income before the generic deduction is €2,100; applying the additional 7% deduction (€147), net income comes to €1,953. That amount falls in the €1,850–2,030 bracket, whose minimum base is €1,209.15. Applying the 31.4% rate, the estimated monthly contribution is about €380. If that same worker were newly registered and entitled to the flat rate, they would pay around €88.64 during the first twelve months, depending on their contribution base.

How to interpret the result

The fee you get is an estimate calculated on your bracket's minimum base, which is what most self-employed workers pay. Three caveats are worth keeping in mind. First, it is a forecast: the definitive figure is reconciled once the tax authority reports your actual income. Second, always contributing on the minimum base lowers your fee today but reduces your future pension and sick-leave benefits, so if your activity is stable it may pay to choose a somewhat higher base. Third, the contribution is a deductible expense on your income tax return, so its real effective cost is lower than the amount you pay each month.

Which expenses you can deduct (and which you cannot)

The contribution is only part of the bill: what you finally pay also depends on the expenses you can deduct. Deductible ones are those linked to the activity, backed by an invoice and recorded in your books: the self-employed contribution itself, materials, software, related training, insurance, professional association fees, accountancy services and the utilities of premises used for the activity. If you work from home, you can deduct the proportional share of the square metres devoted to the activity in ownership costs (property tax, community fees, insurance) and a reduced percentage of the utilities for that same proportion: water, electricity, gas and internet. The vehicle is the most contentious case: except for specific activities such as transport, taxi or sales representatives, the tax agency only accepts full deduction where exclusive professional use is proven, which is hard if it is your only car. Business meals are accepted within daily limits and always paid electronically.

Registration, the flat rate and quarterly obligations

Registration has two steps that cannot be swapped: first the tax agency, with the census registration declaring your activity and tax obligations, and then social security, with a maximum of sixty calendar days before the activity starts. Anyone registering for the first time, or who has not been registered in the immediately preceding years, can usually take the flat rate: a fixed reduced contribution during the first year, extendable for a second year if net earnings stay below the minimum wage. From then on, obligations are quarterly: form 303 to settle output VAT minus input VAT, and form 130 for income tax instalments if you do not mostly invoice companies that withhold tax. At year end you file the annual summaries and the income tax return, where everything is reconciled.