Register as autónomo (self-employed)
Autónomo registration is required for any self-employed work in Spain, including freelancing for foreign clients. It involves registering with both the Tax Authority (Hacienda) and Social Security. Monthly contributions start at €225 (reduced rate).
Official sources
- Agencia Tributaria — Autónomos
Tax authority information for self-employed
- Sede Electrónica — Online Tax Registration
Online filing requires a digital certificate or Cl@ve
The steps
- 1
Register with Hacienda (Agencia Tributaria)
Register your economic activity by filing Modelo 036 or Modelo 037 (simplified form for most freelancers). This declares your activity type (IAE code), your start date, and your VAT (IVA) status. File online via the AEAT Sede Electrónica or in person at your local tax office.
Documents needed
- Valid passport or residence card
- NIE
- Completed Modelo 037 (or 036 for more complex situations)
- Digital certificate or Cl@ve PIN (for online filing)
The IAE code (Impuesto sobre Actividades Económicas) classifies your activity. For tech freelancers and developers, common codes include 763 (IT consulting) or 764 (data processing). Get this right — it affects your quarterly tax declarations. - 2
Register with Social Security — RETA
Within 60 days of registering with Hacienda, register with the INSS under the RETA (Régimen Especial de Trabajadores Autónomos). File form TA.0521. Monthly contributions start at €225 for new autónomos (reducción de cuota de nuevos autónomos) for the first 24 months.
Documents needed
- NIE
- TA.0521 form
- Hacienda registration confirmation
Missing the 60-day window means you owe contributions from the date you first registered with Hacienda — do not delay. - 3
File quarterly VAT and income tax declarations
As an autónomo, you must file quarterly declarations: Modelo 303 (IVA — VAT, every quarter), Modelo 130 (IRPF — advance income tax payments, every quarter), and annual Modelo 390 (VAT summary) and Modelo 100 (income tax return). Most autónomos use a gestor (accountant) for this.
Hiring a gestor costs €30–80/month and is very common. They handle all quarterly filings and provide a stress-significant reduction in administrative load. Worth it.