Tarifa plana in the second year: should you extend it, and how to work it out

For the first 12 months, a self-employed worker (autónomo) pays a fixed, reduced Social Security (Seguridad Social) contribution: the tarifa plana (flat rate). It is currently around €89 a month: €80 plus the mandatory MEI contribution (the intergenerational equity mechanism). It can be extended for another 12 months, but not for everyone and not automatically. Here is how to tell whether it is worth it.

Step 1. Work out your expected net income

Net income is calculated in the same way as for the standard contribution (cuota):

Income from the activity for the year minus the expenses related to it (excluding IGIC or IVA).
Subtract 7% from the result (3% for a company autónomo, autónomo societario).

For details of the calculation, see the article “How to calculate your autónomo Social Security contribution”.

Step 2. Compare it with the SMI

Below €17,094 a year: you can extend.
Above: you cannot extend, and from month 13 your contribution is based on income.
Close to the threshold: you can extend, but if the year turns out better than expected, you will get a recalculation afterwards with an amount to pay. This is not a penalty: you only pay the difference in contributions, with no surcharge if you pay within the deadline in the notice.

Step 3. Work out how much you will save

Compare the tarifa plana (around €89 a month) with the contribution you would pay based on your income. With income below the SMI, these are the contributions on the reduced scale, roughly €200 to €270 a month; the Social Security calculator will show the exact amount.

Example: net income of €12,000 a year, i.e. €1,000 a month. Based on income, the contribution would be about €260 a month. With the tarifa plana it is around €89. The saving is roughly €170 a month, about €2,000 over the year.

When extending may not pay off

Your income is growing and will probably exceed the SMI. You will then get a recalculation with an amount to pay after the year ends, and there will be no saving.
Benefits matter to you. The reduced contribution is calculated on the minimum base, so both sick pay and your future pension for this period will be at the minimum.
The second year spans two calendar years. The threshold is checked for each year separately: if your income exceeds the SMI in one of them, your contribution for that year will be recalculated.

How to apply

The extension application is submitted in Import@ss using a digital certificate (e-signature) or Cl@ve (the government's online ID system), in the section for changing autónomo details, under “Prórroga de la tarifa plana”. In it you declare that you expect your income to be below the SMI. No documents need to be attached.

The key is to apply before the end of month 12. If you miss it, from month 13 your contribution will be based on income, and the extension cannot be applied retroactively.

Would you like us to work out whether the extension pays off for you and submit the application? Write to us.

This is not legal advice. Updated October 2026.