Am I required to register as autonomo to invoice in Spain?

Yes. In Spain, any regular economic activity requires registration with RETA (the Special Regime for Self-Employed Workers) and with the Tax Agency (form 036/037). Invoicing without registration can result in penalties.

What VAT rate should I apply on my invoices?

The standard rate is 21%. Reduced rates exist at 10% (food, transport) and super-reduced at 4% (bread, milk, books). Some activities are VAT-exempt (healthcare, education, insurance).

Can I invoice without being registered if it is a one-off job?

This is a contentious issue. Social Security requires registration from the very first activity. In practice, very occasional and low-amount activities may be declared without RETA registration, but they must always be declared to the Tax Agency.

What is Verifactu and how does it affect me?

Verifactu is the Spanish Tax Agency's system for verifying electronic invoices in real time. It will be phased in and will require your invoicing software to send a hash of each invoice to the tax authority. Using Verifactu-ready software will save you from last-minute migrations.

How often do I need to file VAT returns?

Quarterly for most freelancers (form 303), with a deadline of the 20th of the month following the quarter. Large companies file monthly. The annual summary (form 390) is filed in January.

Complete Guide: How to Invoice as a Freelancer in Spain in 2026

Invoicing as a freelancer in Spain can feel like navigating a maze of tax forms, rates, and deadlines. The reality is that once you understand the rules, the process is straightforward and repetitive. The real problem is not complexity itself -- it is that nobody explains everything in one place, in plain language, with non-Spanish speakers in mind.

This guide covers everything you need: from the prerequisites before you can issue your first invoice, to the quarterly deadlines you cannot afford to miss, to the 12 mandatory data fields every invoice must contain. Whether you are a digital nomad who just moved to Spain, an expat starting freelance work, or simply someone who wants to understand the system properly, you will find the answers here.

Before you invoice: prerequisites

Before issuing your first invoice, there are three mandatory registrations. They are not optional, and the order matters.

Tax Agency registration (form 036/037)

The first step is to notify the Agencia Tributaria (Spanish Tax Agency, also known as AEAT or Hacienda) that you are starting an economic activity. This is done via form 036 (full census declaration) or 037 (simplified version, valid for most freelancers).

During this process, you choose your IAE code (Impuesto de Actividades Economicas), which classifies your type of activity. You also indicate your VAT regime and estimated income.

Registration can be done online with a digital certificate or Cl@ve PIN, or in person at any AEAT office. It is free and takes effect immediately.

Once registered with the Tax Agency, you must enroll in RETA (Regimen Especial de Trabajadores Autonomos), the special Social Security regime for self-employed workers. Since 2023, freelancer contributions are based on real net income brackets, meaning you pay according to what you earn.

For the first months, there is a flat-rate quota of 80 euros per month, available for the first 12 months and extendable to 24 months if your net income does not exceed the minimum wage (Salario Minimo Interprofesional).

Registration is done through the Import@ss portal or in person at a Social Security office.

Choosing your IAE code

The IAE code classifies your economic activity. There are two main groups: professional activities (section two) and business activities (section one). The distinction is important because it directly affects whether your business clients must withhold income tax (IRPF) from their payments to you.

If you are classified as a professional (consultant, designer, developer, lawyer, architect), your business clients are required to apply IRPF withholding on the invoices they pay you. If you are classified as a business (retail, hospitality, construction), withholding typically does not apply.

Issuing invoices before registering with the Tax Agency and Social Security can result in penalties. Registration must be prior to, or at the very latest simultaneous with, the start of your activity. Do not wait until you have your first client to complete it.

The 12 mandatory data fields on an invoice

Spanish invoicing regulations (Royal Decree 1619/2012) define the data every full invoice must contain. Omitting any of them can invalidate the invoice for tax purposes.

Invoice number (sequential, no gaps)
Invoice series (if you use multiple series)
Date of issue
Issuer details: full name or business name and NIF (tax ID)
Recipient details: full name or business name and NIF
Detailed description of services or products
Taxable base (amount before taxes)
VAT rate applied (percentage)
VAT amount (resulting figure)
IRPF withholding, if applicable (percentage and amount)
Total invoice amount
Date of the transaction, if different from the issue date

Numbering deserves special attention. Invoices must follow a sequential order within each series and fiscal year. You cannot have gaps: if your last invoice was 2026-023, the next must be 2026-024. A gap in numbering is one of the first things the Tax Agency checks during an audit.

Types of invoices you should know

Not all invoices are the same. Spanish regulations recognize several types, each with specific requirements and use cases.

Full invoice (factura completa)

This is the standard invoice containing all the data fields listed above. It is mandatory for most business-to-business (B2B) transactions. When someone says "invoice" without further qualification, this is what they mean.

Simplified invoice (factura simplificada)

The equivalent of the old-style receipt or ticket. It can be issued when the total amount does not exceed 400 euros (VAT included) or for certain retail activities. It does not require the recipient's full details -- their NIF is only needed if they request it. Common in retail, hospitality, and transport.

The limit rises to 3,000 euros in specific cases defined in the invoicing regulations, such as retail sales, hospitality services, and parking.

Corrective invoice (factura rectificativa)

Issued to correct errors on a previously issued invoice. You cannot simply delete and redo an invoice once it has been issued: you must issue a corrective invoice that references the original (number and date). The most common reasons are amount errors, product returns, and retroactively applied discounts.

Summary invoice (factura recapitulativa)

Groups multiple transactions with the same recipient within the same calendar month. Very useful when you invoice recurring services or frequent deliveries to the same client. It must be issued before the 16th of the month following the transactions.

VAT: rates and exemptions

VAT (IVA in Spanish, Impuesto sobre el Valor Anadido) is the indirect tax on consumption. As a freelancer, you collect it on behalf of the Tax Agency: you charge it to your clients and remit it quarterly, deducting the VAT you have paid on your own purchases (input VAT).

Current VAT rates in Spain: 21% standard (most products and services), 10% reduced (food, passenger transport, hospitality, renovation works), 4% super-reduced (bread, milk, eggs, fruit, vegetables, books, medicines), and 0% or exempt for activities such as regulated education, healthcare, insurance, and financial services.

A common mistake is applying the reduced rate when it does not apply. When in doubt, the standard 21% rate is always safe. Applying a rate lower than required can trigger a supplementary assessment with surcharges.

IRPF withholding: when and how much

If your activity is classified as professional under the IAE (section two), your business and professional clients must apply IRPF (income tax) withholding on the invoices they pay you. You issue the invoice with the withholding deducted, and the client remits that amount to the Tax Agency on your behalf. It is essentially an advance payment on your annual income tax return.

The standard withholding rate is 15% of the taxable base.

If you have registered as a freelancer for the first time, you can apply a reduced rate of 7% during the year of registration and the following two years. You must notify your clients, and you must not have carried out any professional activity in the previous year. This is a significant cash flow boost in your early years.

Withholding only applies to invoices issued to businesses and professionals. If you invoice individuals (end consumers), there is no IRPF withholding.

Deadlines you cannot forget

A freelancer's tax calendar in Spain revolves around quarterly cycles. Deadlines are non-negotiable, and penalties for late filing are automatic.

Form 303 (quarterly VAT)

This is the quarterly VAT self-assessment. You declare the VAT you have charged (output VAT) minus the VAT you have paid (input VAT). If the result is positive, you pay the difference to the Tax Agency. If negative, you carry it forward to the next quarter or request a refund in the fourth quarter.

Deadlines: April 1-20 (Q1), July 1-20 (Q2), October 1-20 (Q3), and January 1-30 (Q4).

Form 130 (quarterly income tax)

This is the quarterly IRPF installment payment for freelancers on the direct estimation method. You declare 20% of your cumulative net income since the start of the year, minus installments already paid and withholdings suffered.

Deadlines coincide with form 303.

Form 390 (annual VAT summary)

Filed in January (1st to 30th), this is the annual summary of all your VAT transactions. It must match the sum of your four quarterly 303 filings. It does not involve an additional payment, but filing it is mandatory.

In addition to the 390, remember form 347 (transactions with third parties exceeding 3,005.06 euros annually) in February, and form 349 (intra-community transactions) if you work with EU clients or suppliers.

Verifactu: the future of invoicing in Spain

Verifactu is the Spanish Tax Agency's invoice verification system. Its goal is for every invoice issued by invoicing software to be registered immediately (or near-immediately) on the tax authority's servers via a cryptographic hash that guarantees its integrity.

For freelancers, the main impact is that your invoicing software will need to be certified and capable of sending those records. Using spreadsheets or Word documents for invoicing will no longer be viable once the system is fully implemented.

The rollout will be gradual, but the direction is clear: invoicing in Spain will be fully digital and traceable. Freelancers already using Verifactu-ready software will not need to do anything additional when the obligation takes effect. Those still invoicing with manual methods or non-compliant software will have to migrate under pressure.

How to simplify all of this

The volume of requirements, types, forms, and deadlines can seem overwhelming, but the reality is that most of the work is repetitive and automatable. Every quarter you do the same thing: sum invoices, calculate VAT and income tax, file forms. It is a mechanical process that software can resolve in seconds.

Frihet automates invoicing for freelancers and SMEs in Spain. Every invoice you issue automatically includes the 12 mandatory data fields, calculates VAT and IRPF withholding based on your setup, maintains sequential numbering without gaps, and stores everything ready for your quarterly filings.

Start invoicing with proper software from day one. Migrating data from spreadsheets to an ERP after months or years is painful and error-prone. If you are just starting as a freelancer in Spain, this is the best time to get it right from the beginning.

Tax compliance does not have to be your enemy. With the rules clear and the right tools in place, invoicing as a freelancer in Spain is a predictable, controllable, and -- most importantly -- automatable process. Spend your time on what truly matters: growing your business.