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Module 4 of 7 · 20 min

Contribution bases and the IRPF base

Free payslip course: read the module, review with the questions and move on to the next one. At the end, a test and a PDF certificate.

Module 4 of 7 · Course contents

At the bottom, under «Determinación de las bases», the payslip shows the amounts the deductions are calculated on. It is the hardest part to read and the one that matters most for your unemployment benefit, sick pay and pension.

Common contingencies base (BCCC)

  • It is the total monthly pay, in money and in kind, you are entitled to that month (or what you actually get if it is higher), plus the proportional share of the extra payments and of items paid less often than monthly (LGSS, article 147.1).
  • The share is worked out by dividing the yearly amount of the extra payments by 12 if you are paid monthly, or by 365 and multiplying by the days of the month if you are paid by the day (Order PJC/297/2026, article 1).
  • Not included (article 147.2): public-transport travel expenses with an invoice; per diems and travel, meal and accommodation expenses within the IRPF limits; compensation for death, transfers, suspensions and dismissals (within the legal limits); Social Security benefits and sick-pay top-ups; study costs required by the job; and overtime, except for work accidents.
  • If the result is below the minimum base of your group or above the maximum, contributions are paid on the minimum or the maximum (Order PJC/297/2026, article 1; LGSS, article 148). In 2026 the maximum cap is €5,101.20 a month (article 2).

Occupational contingencies base (accidents and occupational disease, unemployment, FOGASA and training)

It is the same as the common contingencies base plus overtime (LGSS, article 147.2.e), with the same cap. Unemployment, FOGASA and vocational training contributions are calculated on it (Order PJC/297/2026, article 33.1).

Base subject to IRPF withholding

It is total earnings minus the payments exempt from IRPF (per diems and travel expenses within the limits of the Regulations, certain compensation). It is usually different from the contribution base: overtime is taxed, and part of the per diems may be subject to contributions but not to tax, or the other way round.

In practiceYou earn €1,600 a month plus two extra payments of €1,600. Your common contingencies base is not 1,600 but 1,600 + (3,200 / 12) = €1,866.67. If you did €100 of overtime that month, the occupational contingencies base is €1,966.67. Check it against your Social Security contribution bases report.

Source: Ley General de la Seguridad Social (Real Decreto Legislativo 8/2015; General Social Security Act, in Spanish), articles 147 and 148 · Orden PJC/297/2026, cotización a la Seguridad Social para 2026 (2026 contribution rules, in Spanish), articles 1, 2 and 3

Quick review

Check that you've understood. These are questions from the final test: tap an answer to see whether it's right and why.

How are the extra payments included in the common contingencies contribution base?

Is overtime included in the common contingencies base?

If your contribution base comes out above the maximum base of your group, what do you contribute on?

Module practice test

6 new questions, different from the final test. Tap an answer to see whether it is right, why, and which rule it comes from.

1. If you are paid monthly, what is the yearly amount of the extra payments divided by to spread it over the base?

2. Are public-transport travel expenses with an invoice included in the contribution base?

3. Which base is used for unemployment, FOGASA and vocational training contributions?

4. If the calculated base is below the minimum base of your group, what are contributions paid on?

5. Who sets the maximum contribution base cap every year?

6. How do accrued holidays not taken and paid when the contract ends carry contributions?

Course contents