How to register as a freelancer: step-by-step

Starting a business in Spain involves completing several legal procedures that can seem complex at first. However, registering as a freelancer is the essential first step to turning your business idea into a legally and fiscally compliant enterprise.

With over 3.35 million self-employed workers in Spain, freelancing has become the go-to option for freelancers, independent professionals, and small business owners. That said, it’s important to note that being a freelancer is not the same as being a business owner—entrepreneurs often manage larger operations and face different legal obligations.

If you plan to carry out an economic activity personally and regularly, registering as a freelancer is legally mandatory, regardless of how much income you expect to earn.

In this comprehensive guide, we’ll walk you through every step of the registration process—from initial requirements to the formalities you need to complete with the Tax Agency and Social Security. You’ll also find practical tips to avoid common mistakes and make the most of available financial incentives and bonuses.

Summary

1. What does it mean to be a freelancer in Spain?
2. Requirements to register as a freelancer in Spain
3. When to register as a freelancer: key deadlines
4. Step 1: registering with the Spanish tax agency (Hacienda)
5. Required documentation for tax agency registration (Hacienda)
6. Step 2: registering with Social Security (RETA)
7. Real income-based contribution system (2025)
8. Additional procedures depending on the type of activity
9. Practical tips before registering as a freelancer
10. Practical tips after registering as a freelancer
11. Common mistakes when registering as a freelancer
12. Startup and maintenance costs for freelancers in 2025
13.  Bonuses and support for new freelancers

What does it mean to be a freelancer in Spain?

Getting started: freelancing as the first step to entrepreneurship

Becoming a freelancer is more than just registering with government databases. It’s a conscious decision to take full control of your professional life, embracing both the freedom and the responsibilities that come with it. For many entrepreneurs, registering as a freelancer marks the official beginning of their business journey.

Thinking about going freelance in Spain? Whether you're chasing independence or launching your first business, freelancing is often the first big step. Learn what it really means, how to register, and what to expect in our article Freelancers explained: all you need to know.

Legal definition of a freelancer under Spanish law

According to Spanish legislation, a freelancer (autónomo) is a natural person who habitually, personally, and directly performs an economic activity for profit, without being bound by an employment contract. This definition highlights several key differences between freelancers and salaried employees.

The legal framework governing freelancers is the Special Regime for Self-Employed Workers (RETA), part of the Social Security system. Freelancers must meet both tax and contribution obligations from the moment they start operating and are accountable to both the Tax Agency and Social Security.

You can register for RETA online or in person at a Social Security office. Additionally, you must choose a mutual insurance provider to cover common and work-related risks.

Main differences between freelancers and employees

• No minimum capital requirement: Freelancers don’t need a minimum investment to start, but they are personally liable for any business debts.
• Independence: Freelancers are free to organise their work, schedules, and methods.
• Personal liability: They are personally responsible for business-related debts (except in the case of limited liability freelancers).
• Social contributions: Paid through the RETA, not the General Social Security scheme.
• Taxation: Income is taxed under IRPF (personal income tax) as business income, not employment income.
• Benefits: Freelancers access specific welfare benefits, under different conditions than employees.

Freelancer flexibility and responsibilities

Flexibility

• Full control over your schedule and working hours
• The ability to choose your clients and projects
• The freedom to grow your business and hire staff
• Flexibility in where you work—from home, an office, or abroad

Responsibilities

• Full administrative and accounting management
• Compliance with tax and labour obligations
• Unlimited personal liability (unless registered as a limited liability freelancer)
• Self-managed pension and social security contributions

Legal, tax, and contribution duties

Upon registration, freelancers must take on a variety of obligations:

• Tax: Filing quarterly and annual returns for VAT, IRPF, and informative forms
• Accounting: Maintaining accurate records of invoices issued and received, and expense tracking
• Labour: Complying with employment law if hiring staff
• Social Security: Paying monthly contributions
• Invoicing: Issuing legally compliant invoices

Staying up to date on legal and tax updates is essential. Ongoing training and professional advice are critical to ensuring your business remains compliant and to take full advantage of available tax deductions and state support.

Requirements to register as a freelancer in Spain

Be at least 18 years old

The first and most basic requirement is reaching the legal age of 18. Minors under 18 can only register as freelancers if they are legally emancipated, which requires either judicial or notarial authorisation, depending on the circumstances.

Some situations that allow emancipation include:

• Marriage
• Parental authorisation
• Court decision

Key documents required for registration include:

• A valid DNI (for Spanish nationals) or NIE (for foreigners)
• The economic activity code (CNAE/IAE)
• The start date of the activity
• A bank account for direct debit payments

Hold a valid DNI or NIE

Every applicant must have a valid tax identification number:

• Spanish citizens: Valid DNI
• Foreign nationals: Valid NIE (Foreigner Identification Number)

For foreign nationals: valid work and residency permits

Non-EU nationals must provide:

• A valid residency permit
• Authorisation to work as self-employed
• Proof of being legally resident in Spain

In some cases, long-term residency and continuous work may support Spanish nationality applications.

EU citizens have the right to reside and work in Spain, but must register officially if their stay exceeds three months.

No professional or legal incompatibilities

Before registering, it’s important to confirm that there are no restrictions based on your current status:

• Public sector workers: Often barred from engaging in private business.
• Salaried employees: Must review contracts for exclusivity clauses.
• Pensioners: Some pensions may be incompatible with business activity.
• Welfare recipients: Certain benefits restrict or reduce eligibility when working independently.

Clearly define the activity you will perform

Knowing exactly what economic activity you will undertake is crucial. It determines:

• The correct IAE (Economic Activity Tax) category
• Any licences or permits required
• The most suitable tax regime
• Applicable contribution base and rates

Identifying the right IAE and CNAE codes is essential, as they must be reported to both the Tax Agency and Social Security during registration.

Have a bank account for direct debit payments

You will need a bank account to:

• Pay your monthly freelance contributions
• Settle quarterly tax returns
• Receive tax refunds, if applicable

Note: If you are registering a company, you must have a CIF (tax ID number) to open a business bank account.

Many freelancers choose to open a separate account dedicated to their professional activity to keep personal and business finances clearly separated.

Keep your finances clear from the start. Open a dedicated freelancer account to manage taxes, contributions, and refunds with ease.

When to register as a freelancer: key deadlines

You must register before or on the day you start working

Spanish law is strict about timing: you must register as a freelancer before starting any economic activity. This means you cannot invoice or carry out any business operations until your registration is complete. Freelancers can register up to 60 calendar days in advance to avoid late payment surcharges.

60-day window for social security registration

You can register with Social Security within a defined period:

• From 60 calendar days before the official start date of your activity
• Up to and including the day your activity begins

This timeframe is strictly enforced and exceptions are not allowed.

What happens if you miss the deadline?

Registering late can result in several consequences:

• Fines ranging from €60 to €6,000, depending on the severity
• Surcharges of 10% to 20% on unpaid contributions
• Late interest charges, calculated daily from your actual start date
• Back payments: You may be required to pay contributions retroactively from when you actually started working

Loss of benefits for late registration

Missing the deadline also means forfeiting key financial benefits:

• Flat-rate fee (tarifa plana): Only available if registration is done on time
• Regional incentives: Many require punctual registration
• Unemployment benefit capitalisation: Irregularities in timing may disqualify you

Why coordinating with both agencies is critical

Both the Tax Agency and Social Security must be informed of your start date. To ensure full compliance:

• Register with both entities on the same day or within a few days
• Make sure start dates match across both registrations
• Keep proof of registration from both institutions

Step 1: registering with the Spanish tax agency (Hacienda)

Registering with the Tax Agency is a mandatory first step for any freelancer or entrepreneur starting an economic activity in Spain. This process involves submitting a census declaration (Forms 036 or 037) to report your personal details, business activity, and applicable tax regime.

The good news? This registration can be completed online via the official website of the Spanish Tax Agency, making it much easier and faster. You can submit Forms 036 or 037 through the AEAT electronic headquarters using a digital certificate or the Cl@ve PIN system.

Important: You must be registered in the Census of Entrepreneurs before starting to work.

Submitting form 036 or 037 (Census Declaration)

The first official step is the census declaration using Form 036 or 037, which registers you in the Census of Entrepreneurs, Professionals and Withholders. This makes you an official taxpayer for economic activities.

Documents required:

• Form 036 or 037
• DNI/NIE
• Business address
• IAE and CNAE codes for your activity

Form 036 vs. form 037: what’s the difference?

Form 036 (Full version)

• For all types of activities and business setups
• Required if you have multiple activities or plan to hire employees
• Necessary for special tax regimes

Form 037 (Simplified version)

• Only for individuals with a single, simple activity
• No employees
• For those under simplified direct estimation or module regimes

Choosing the right IAE code (Impuesto de Actividades Económicas)

Selecting the correct IAE code is crucial, as it defines:

• Applicable tax deductions
• Module regime coefficients
• Sector-specific obligations
• Potential future incompatibilities

Every activity has a specific 3-digit IAE code to classify economic activity. You must also report the relevant CNAE code, used in both tax and Social Security registrations.

Tip: Use the official code list on the AEAT website, or consult a tax advisor.

Selecting the appropriate VAT regime

You must choose one of the following:

• General regime – Applies to most professionals and businesses
• Simplified regime – For small businesses with limited turnover
• Equivalence surcharge – For certain retail trade activities
• Exemption – Some professional services are VAT-exempt

Choosing the IRPF regime (Direct Estimation or Modules)

There are three main income tax options.

Normal Direct Estimation:

• For annual income above €600,000
• Full accounting obligations
• Higher administrative complexity

Simplified Direct Estimation:

• For most freelancers
• Fewer accounting duties
• Income below €600,000 per year

Objective Estimation (Modules):

• Only for activities listed in official annexes
• Income is estimated based on objective parameters
• Useful for high-income, low-expense business types

Online or in-person processing

Since 2023, many tax procedures are mandatory online.

To register electronically, you need:

• A digital certificate or Cl@ve PIN
• Access to the AEAT website
• Basic familiarity with official government portals

Required documentation for tax agency registration (Hacienda)

To register as a freelancer with the Spanish Tax Agency, you must provide the following documents:

1. Original and Copy of DNI or NIE

You must present:

• The original identification document for verification
• A certified or verified photocopy
• The document must be valid and up to date

2. Completed Form 036 or 037

The form must include:

• Full personal details
• NIF (Tax Identification Number)
• Fiscal address (can be your personal residence)
• A detailed description of your economic activity
• Start date of the activity
• The selected tax regime

3. Activity-Specific Supporting Documents

Depending on your profession or business, you may need to submit:

• Professional qualifications or licences
• Certificates of competence
• Sector-specific authorisations or permits
• Lease agreements or documentation for physical business locations

4. Proof of Fiscal Address

To verify your fiscal address, provide one of the following:

• Utility bill (electricity, water, or gas)
• Lease contract or property deed
• Certificate of residence (empadronamiento)
• Recent bank statement showing your address

Step 2: registering with Social Security (RETA)

Enrolling in the special regime for self-employed workers (RETA)

Once you’ve completed your registration with the Tax Agency, the next step is to enrol in RETA, the special Social Security scheme for freelancers. This establishes your legal status as a self-employed worker and determines your monthly contribution obligations.

How to register: online via Importass or in person

You can complete your RETA registration in one of two ways:

Online (Recommended)

• Through the Importass portal (Social Security’s digital platform)
• Available 24/7
• Instant confirmation of your registration
• Requires a digital certificate or Cl@ve PIN

In person

• At a Social Security office
• Appointment required
• Limited office hours apply

Submitting form TA.0521 or online application

You’ll need to complete Form TA.0521, which includes:

• Personal information
• Your economic activity
• The contribution base you choose
• Your official start date
• Your selected mutual insurance provider (mutua colaboradora)

Choosing a contribution base 

Since 2023, Social Security contributions are based on net monthly income brackets. You can adjust your contribution base up to six times a year.

Requesting available discounts (Flat Rate)

The flat-rate plan for new freelancers in 2025 offers:

• €87.60/month during the first 12 months
• A possible 12-month extension under certain conditions
• Requirement: You must not have been registered as a freelancer in the previous 2 years

Selecting a mutual insurance provider (Mutua)

Choosing a mutual insurance provider is mandatory to cover:

• Work-related accidents and illnesses
• Common illnesses
• Temporary incapacity

Popular options include:

• Mutua Universal
• Fremap
• Activa Mutua, among others

Real income-based contribution system (2025)

How the new system works: based on net income

The current system links Social Security contributions to the freelancer’s actual net income, as reported in the previous year’s IRPF (personal income tax return). This marks a major shift from the previous system of fixed contribution bases, aiming to create a fairer model where contributions align more closely with earnings.

Contribution brackets and corresponding bases

The system is divided into 15 income brackets, ranging from €670 to over €6,000 per month. Each bracket has its own minimum and maximum contribution base, ensuring that freelancers contribute in proportion to what they earn.

Flat rate of €87.60 for new freelancers in 2025

This flat-rate discount represents a substantial reduction from the standard monthly fee and is designed to support new entrepreneurs. To qualify, you must:

• Not have been registered as a freelancer in the previous 24 months
• Be up to date with Social Security payments
• Remain actively self-employed for at least 12 months

Flexibility to adjust your contribution base

Freelancers can request changes to their contribution base up to six times per year, with the new base taking effect from the following month. This allows freelancers to adapt contributions to fluctuations in income throughout the year.

Additional procedures depending on the type of activity

In Spain, freelancers and companies may be required to complete additional procedures depending on the type of activity they intend to carry out. These requirements vary based on sector-specific regulations and the legal form of the business. For instance, if your activity involves opening a public-facing premises, you must apply for construction and business licences through your local town hall.

Notifying the regional government of your workplace opening

If you’re opening a physical workplace with employees, you are legally required to notify the labour authority of your Autonomous Community.

Tip: This process is independent from municipal permits and focuses on occupational health and safety regulations.

Applying for local business licences

If your activity involves operating a commercial premises, you’ll need to obtain:

Opening Licence:

• Issued by the local council
• Ensures compliance with urban and zoning regulations
• Usually requires a technical inspection of the premises

Environmental Licence:

• Required for activities with potential environmental impact
• Varies depending on the nature of the business
• May require additional technical assessments or reports

Registration with a professional association (if applicable)

Certain regulated professions require mandatory registration with a professional body:

• Examples: Architects, doctors, lawyers, engineers
• Always verify whether your activity requires registration
• Some associations offer freelancer-specific membership options

Health and food safety registration (for food-related activities)

If your business involves food handling or production, you must comply with strict hygiene and health regulations to protect public health. Required steps include:

• Registration with the Sanitary Registry of Food Businesses (RSIPAC)
• Food handling certification course
• Premises compliance certificates
• Hazard Analysis and Critical Control Points Plan (HACCP)

Other activity-specific authorisations

Depending on the sector, other specific licences or authorisations may apply:

• Transport: Public transport authorisation
• Security: Permits for private security services
• Healthcare: Specialised sanitary authorisations
• Education: Authorisations for private educational institutions

Practical tips before registering as a freelancer

Plan ahead and avoid last-minute stress

Good preparation helps you avoid mistakes and unnecessary delays:

• Begin the registration process at least 30 days before your planned start date
• Gather all the required documentation in advance
• Obtain a digital certificate or Cl@ve PIN in good time
• Schedule registrations and paperwork on working days to avoid system delays

Assess the financial viability of your business

Before registering, conduct a thorough financial analysis:

• Estimate your expected income for the first 12 months
• List all fixed costs (e.g. Social Security contributions, rent, utilities)
• Include variable expenses (e.g. supplies, subcontracting)
• Add a financial buffer to cover unexpected costs

Calculate expected income accurately

To select the right contribution base:

• Review any confirmed projects or clients
• Factor in seasonal fluctuations of your business
• Be realistic about growth expectations
• Remember: you can adjust your contribution base up to 6 times per year

Research available grants and subsidies

Explore funding opportunities at different levels:

• National: ICO, ENISA loans, SEPE programmes
• Regional: Grants from Autonomous Communities
• Local: Support from city councils and provincial governments
• European: EU structural funds and entrepreneurship initiatives

Consider compatibility with unemployment benefits

If you are receiving unemployment benefits:

• Partial compatibility: You may be able to keep part of your benefit while working
• Lump sum (capitalisation): You can request to receive your remaining benefit as a single payment
• Always check specific eligibility conditions to avoid issues

Consider hiring a professional advisor (Asesoría)

A tax and business advisor can help with:

• Full tax and accounting management
• Handling registrations and updates
• Strategic business advice
• Representing you before official institutions

Typical cost: €60 to €300 per month, depending on the level of service.

Practical tips after registering as a freelancer

Set up accounting and invoicing systems from day one

Establishing good systems early will save time and prevent errors later.

Accounting:

• Maintain a record of income and expenses
• Archive all invoices issued and received
• Track investments and depreciation
• Monitor payments to suppliers and incoming payments from clients

Invoicing:

• Use invoicing software suited to your needs
• Apply sequential invoice numbering (mandatory)
• Include all required tax details (NIF, VAT breakdown, etc.)
• Keep copies of all invoices issued

Meet quarterly tax obligations

The Spanish tax calendar includes mandatory quarterly submissions.

Regularly review your contribution base

It’s recommended to:

• Reassess quarterly whether your current base fits your income
• Consider adjustments based on your business growth
• Remember: higher contributions = better future benefits

This is especially relevant for retirement planning, as your chosen base directly impacts your future pension.

Keep business documentation up to date

You should retain:

• Proof of registration with Hacienda and Social Security
• All quarterly and annual tax filings
• All invoices and receipts for at least 4 years
• Client and supplier contracts
• Employment documents (if you hire staff)

Take advantage of permitted tax deductions

Common deductible expenses include:

• Utilities: Electricity, water, gas, phone, internet
• Office supplies: Laptops, software, furniture
• Training: Courses related to your business activity
• Transport: Professional vehicle use, mileage
• Workplace costs: Rent, mortgage (proportional if working from home)

Plan for growth and future business changes

As your business evolves, consider:

Hiring employees: Be aware of additional labour obligations

Converting to a limited company (SL): This can offer limited liability, attract partners, and support growth.

• A standard SL requires a minimum capital of €3,000
• A "SL with €1 capital" is possible under certain conditions

Expanding activities: You’ll need to register new IAE codes

Going international: Be aware of cross-border tax implications

Common mistakes when registering as a freelancer

1. Registering after starting economic activity

One of the most frequent—and serious—mistakes:

• Consequences: Fines, late payment surcharges, and interest
• Solution: Plan to register at least 15 days before your intended start date
• Prevention: Mark key deadlines in your calendar

2. Failing to request the flat rate during registration

The flat-rate contribution must be requested at the time of registration:

• Mistake: Many freelancers try to apply for it later
• Reality: You can only request it during the registration process
• Consequence: Loss of up to 12 months of reduced contributions

3. Choosing the wrong IAE code

Selecting an incorrect IAE code can:

• Limit access to certain tax deductions
• Prevent you from using simplified regimes (modules)
• Create incompatibilities with grants or support schemes

Incorrect IAE and CNAE codes can cause tax and admin issues, as they define your professional activity for both Hacienda and Social Security.

Tip: Always consult a tax advisor before selecting your codes.

4. Miscalculating expected income and contribution base

Common errors include:

• Being overly optimistic about early income
• Ignoring seasonal trends in your business
• Forgetting fixed costs when calculating net income
• Overlooking how the contribution base impacts future benefits (e.g. pensions, sick leave)

5. Not declaring your home office in form 036

If you work from home:

• You are legally required to declare your home address as your fiscal residence in Form 036
• You may be able to deduct a portion of household expenses
• You must keep receipts and bills for electricity, internet, etc.

6. Not requesting unemployment compatibility in time

If you’re receiving unemployment benefits:

• You must request compatibility before you start working
• Specific documentation is required
• Your income must stay within set limits to keep the benefit

7. Overlooking pre-registration expenses

Certain expenses made before registering can be tax-deductible:

• Equipment or materials purchased in preparation
• Training related to your future activity
• Business setup costs (e.g. website, design, consultancy)

Keep all invoices from several months prior to your official start date.

8. Ignoring quarterly tax obligations

Many new freelancers are unaware that they must:

• File quarterly tax returns, even with zero income
• Respect strict submission deadlines to avoid fines
• Keep updated accounting records
• Submit Form 347 if operating with third parties above a certain threshold

Startup and maintenance costs for freelancers in 2025

When launching your freelance activity, it’s essential to have enough initial capital to cover setup expenses and the first few months of operations. This will help you manage registration costs, materials, rentals, and other critical business needs.

Registration costs: free at Hacienda and Social Security

There are no direct fees for the official registration process:

• Tax Agency (Hacienda): Free submission of Form 036 or 037
• Social Security (RETA): Free registration
• Mutual insurance provider (mutua): No cost for affiliation

However, you may encounter indirect costs:

• Digital certificate: €13–25 (valid for several years)
• Travel expenses (for in-person appointments)
• Time invested in managing paperwork

Monthly freelance contributions (from €200 to €800)

The 2025 income-based system sets progressive contribution bands:

Flat rate: €87.60 for the first 12 months

This introductory discount offers substantial savings:

• Annual savings: Between €1,350 and €8,500, depending on your income bracket
• Duration: 12 months guaranteed
• Extension: Additional 12 months if income stays below 2x the national minimum wage

Advisor fees (between €60 and €300 per month)

Tax and business advisory services vary by package:

Basic package (€60–100/month):

• Quarterly tax filing
• Annual income tax return
• Basic fiscal advice

Full service (€150–300/month):

• Full accounting management
• Electronic invoicing setup
• Labour advice (if hiring)
• Representation before government bodies

Licences and permits (activity-dependent)

Variable costs depending on your business sector:

• Opening licence: €200–2,000 (depending on premises size/type)
• Health registry (e.g. for food businesses): €50–300
• Professional association fees: €50–200 annually
• Professional insurance: €200–1,500 annually
• Company registry (if forming a company): €40–100

Bonuses and support for new freelancers

The flat-rate scheme is a key incentive for first-time freelancers in Spain, offering a reduced Social Security contribution to ease the financial burden at the start of the activity.

Key requirements

To be eligible for the flat rate, you must:

• Not have been registered as a freelancer in the previous 24 months
• Be up to date with all Social Security payments
• Have no outstanding debts with the Tax Agency (Hacienda)
• Maintain your freelance activity throughout the bonus period

Duration

• 12 months at a flat rate of €87.60/month
• Possible extension to 24 months if your income remains below 2x the minimum wage