Starting a business in Spain
Alta at two offices makes you an autónomo - the tarifa plana softens the landing, and the income-based contribution tramos are the number to plan around.
Checked against the sources on 2026-08-30
Before anything else
Becoming self-employed in Spain is two registrations in the right order on the same day: the tax office (alta censal at the AEAT) and social security (alta in RETA). Both are free; both are online with a digital certificate or Cl@ve, and getting that credential first is the real step one.
Since 2023 autónomo contributions are income-based: you forecast your net monthly income, land in a tramo, and pay accordingly (roughly €200-590 a month across the ordinary bands), with a settlement against reality the following year. New autónomos instead get the tarifa plana - a flat ~€80 a month for the first twelve months, extendable to twenty-four below the minimum wage.
The legal shell
Autónomo or SL?
Autónomo
The default start. Fast, free, and the tarifa plana applies to people, not companies.
~€80/month year one; income-based tramos after.
Contributions are due monthly regardless of results once registered, and liability is personal.
SL (sociedad limitada)
Liability, partners, or an employer who insists on invoicing a company.
Capital from €1 since 2022 (with personal liability top-up rules until €3,000 is reached); notary and registry roughly €400-800, or the CIRCE fast track online.
A working administrador usually still registers as autónomo societario - at a higher minimum tramo and with no tarifa plana.
The sequence
Get the digital certificate
Where: FNMT, or Cl@ve at any registration officeTakes: Days - do it first
Nearly every filing after this point assumes you can sign online. The certificado digital from the FNMT is the durable option.
Alta censal at the AEAT
Where: Modelo 036 (or the simplified 037), online
You declare the activity under an IAE heading, the start date, and your VAT position. Spain has historically had no small-business VAT exemption - IVA applies from the first invoice - though the EU franchise regime may change this; check the current state.
Certain professional services to businesses invoice with IRPF withholding (retención, 15%, or 7% for new professionals) - your client pays part of your income tax for you.
Alta in RETA
Where: Import@ss, the social security portalTakes: Must be done before or on the AEAT start date
You pick the forecast income band; the tarifa plana is claimed here. You can adjust the band several times a year as reality diverges from the forecast.
Watch out: Order matters: RETA alta after the activity has visibly started can void the tarifa plana and draw a back-charge.
Invoice and file the quarterly cycle
Quarterly IVA (modelo 303) and IRPF payments on account (modelo 130, unless enough of your income carries retención), plus annual summaries. A gestoría handles the lot for €50-100 a month, and nearly every autónomo uses one.
What it costs to start
| What | Amount |
|---|---|
| RegistrationsBoth altas are free. | €0 |
| Tarifa planaFirst 12 months; extendable below minimum wage. | ~€80/month |
| Ordinary tramos afterBy forecast income, settled against reality. | ~€200-590/month |
| GestoríaThe customary way to survive the quarterly cycle. | €50-100/month |
| SL formationLess via CIRCE; capital from €1. | €400-800 |
The words on the forms
- Autónomo
- The self-employed worker; also the name of the whole regime.
- RETA
- The special social-security scheme for the self-employed.
- Modelo 036/037
- The tax census form that opens the activity.
- Tarifa plana
- The ~€80 flat contribution for new autónomos.
- Tramos
- The income bands that set contributions since 2023.
- Retención / IRPF
- Income-tax withholding your business clients apply to professional invoices.
- Gestoría
- The admin/accounting service most autónomos pay monthly.
- IAE
- The activity classification you register under.
The traps
- Doing the RETA alta late and losing the tarifa plana.
- Forgetting IVA applies from the first invoice - there is no comfortable threshold to hide under.
- Setting the income forecast carelessly and meeting a settlement bill a year later.
- Ignoring the falso autónomo rules when one client supplies desk, hours and direction.
Where to check this yourself
This is a map, not legal or tax advice - and an honest one about how it was drawn: the Germany guide was written by a person who walked the route; most other countries were drafted with AI against the official sources and have not yet been walked by someone who did it. Laws change. Every guide carries the date it was last checked and the sources to check it yourself - and if you have been through one of these routes, your corrections are exactly what this handbook wants.