Autónomo in Spain: The Complete Step-by-Step Guide for Foreigners

Yes. The NIE (Número de Identificación de Extranjero) is the tax identification number every foreigner needs to carry out an economic activity in Spain, and it must be obtained before you can register with Social Security (RETA) or file the census declaration with the Agencia Tributaria (Modelo 036/037). EU citizens obtain it alongside their certificado de registro de ciudadano de la UE; non-EU citizens obtain it from a Spanish consulate abroad or a Oficina de Extranjería/police station once in Spain, and it is usually a prerequisite for the residence and work authorisation itself if you are moving to Spain specifically to work as autónomo.

The standard sequence is: (1) obtain the NIE; (2) if required, secure residence/work authorisation for non-EU nationals (or the EU citizen registration certificate); (3) file the census declaration (Modelo 036 or the simplified Modelo 037) with the Agencia Tributaria, declaring your IAE economic activity code, tax obligations and fiscal domicile; (4) register with the Tesorería General de la Seguridad Social under the Régimen Especial de Trabajadores Autónomos (RETA), choosing your monthly contribution base; (5) if applicable, apply for the tarifa plana reduced rate at the same time as the RETA registration. Registering with the AEAT before RETA (or vice versa) is common in practice, but both must be completed before you start invoicing.

Since the RETA reform under Real Decreto-ley 13/2022, new autónomos pay a flat monthly Social Security contribution of approximately €80/month for the first 12 months, regardless of income. This period extends to 24 months total if, during months 13-24, your net income remains below the Salario Mínimo Interprofesional (SMI). The reduced rate applies to genuinely new registrations — it is not available if you were registered as autónomo in the same or a similar activity within the previous 2 years (3 years if you previously benefited from the tarifa plana itself).

Every quarter (20 April, 20 July, 20 October, 30 January), most autónomos file Modelo 303 (IVA/VAT settlement) and Modelo 130 (IRPF advance payment on account, direct estimation regime) under the Ley 37/1992 del IVA and the Ley 35/2006 del IRPF respectively. If you invoice other businesses or professionals subject to withholding, Modelo 111 (retenciones e ingresos a cuenta) is also due quarterly. Annually, this is closed out with Modelo 390 (IVA annual summary), Modelo 100 (IRPF annual income tax return, filed April-June) and, if applicable, Modelo 190 (annual retention summary).

Yes, under the estimación directa (direct estimation) regime — the standard regime for most autónomos — deductible expenses include: RETA social security contributions, office/coworking rent, professional supplies, business-related travel, a proportional share of home-office costs (following AEAT criteria on the percentage of the home used exclusively for the activity), and professional services (gestoría, legal fees). Expenses must be duly invoiced, linked to the economic activity, and recorded in the mandatory VAT and income books (libros registro) under the Reglamento del IRPF.

RETA contributions and the obligation to file quarterly Modelo 303/130 (even as a nil declaration) continue to accrue until you formally deregister — via Modelo 037/036 baja censal with the AEAT and the corresponding baja with the Tesorería General de la Seguridad Social. Failing to file the required quarterly declarations, even at zero activity, can trigger late-filing surcharges (recargos) under the Ley General Tributaria, so formal deregistration on both sides is essential the moment you stop your economic activity.