Registering as self-employed in Spain: the two procedures, in order and without fines

There is no income threshold: registration starts with your first transaction

The first question is whether you have to register in order to invoice a couple of small jobs. You do, and the test in the law is not money. Article 305.1 of the consolidated text of the General Social Security Act (Ley General de la Seguridad Social) includes in the Special Scheme for Self-Employed Workers anyone who carries out "on a habitual, personal and direct basis, on their own account and outside the direction and organisation of another person, an economic or professional activity for profit". Read in full, that paragraph does not contain a single amount: the test is habitual activity.

That is where the most repeated misunderstanding comes from: that anyone earning less than the minimum wage does not have to register. Court rulings have used it as evidence of habitual activity in particular cases, but it is not a written rule and it exempts you from nothing.

The tax agency works the same way. Article 9.4 of the General Regulation on tax management and inspection procedures (Real Decreto 1065/2007) requires the census registration declaration to be filed before the activity begins, and it defines that beginning: it happens "from the moment any supply, service or acquisition of goods or services is made, any payment is received or made, or any employee is hired" with a view to taking part in production or distribution. Buying the computer you are going to work with already counts.

The other myth is a tax one: that below 85,000 euros you can invoice without VAT. Spain has not introduced that exemption and the Spanish VAT Act does not contain it, as the guide on invoicing without VAT below 85,000 euros explains. The glossary entry for autónomo and the page for new freelancers set out the starting point.

The two procedures, the order they go in and the deadline for each

Registering is not one procedure but two, at two administrations that do not talk to each other: the census declaration before the Agencia Tributaria, Spain's tax agency, and registration in the RETA before the Tesorería General de la Seguridad Social, the social security treasury. Both go before you start. No rule says which comes first; in practice the census declaration goes first, because the social security registration will ask you for the activity that determines your inclusion, the one you have just declared to the tax agency (article 46.3 of the General Regulation on the registration of employers and affiliation, Real Decreto 84/1996).

The deadlines are not symmetrical, and that is what trips people up. The modelo 036 is filed before you begin, with no limit on how early. Registration in the RETA is also filed in advance, but with a ceiling: article 32.3.1 allows it at most 60 calendar days before the planned start. That is maximum notice, not a grace period.

One detail almost nobody has updated: the deadline for reporting a deregistration or a change of details went back to six calendar days on 1 August 2026, under Real Decreto 643/2026. It had been three since 2015.

The tax agency: the modelo 036, and why the 037 no longer exists

Start with what you no longer have to do. The modelo 037, the simplified census declaration, has been abolished: Orden HAC/1526/2024 emptied articles 14, 15 and 16 and Annex II of Orden EHA/1274/2007 with effect from 3 February 2025, and since then article 1 of that order approves a single form, the 036. If a page tells you to file the 037, it is out of date.

The 036 can be filed on paper or online, and for an individual it does not require an electronic certificate except in the cases listed in article 12.2 of that order (companies, large taxpayers, REDEME, VAT ledgers kept online): signing with an access code obtained in a prior enrolment is enough.

What matters about the 036 is not the boxes but the decisions you lock in while filling it:

• The IAE activity code, the epígrafe. Section 1 covers business activities, section 2 professional activities carried on by an individual and section 3 artistic ones (rule 3 of the Instruction to Real Decreto Legislativo 1175/1990). Whether your invoices carry withholding depends on that section.
• Your VAT regime and, where relevant, the waiver of estimación objetiva, the flat-rate modules method, and of estimación directa simplificada, the simplified direct assessment of income tax (article 9.3 of Real Decreto 1065/2007).
• Inclusion in the register of intra-EU operators, if you are going to invoice businesses elsewhere in the EU.
• The start date, which fixes the first quarter in which you file the modelo 303, the quarterly VAT return.

On the IAE, the local tax on economic activities, there are two exemptions. Individuals, resident or not, are permanently exempt from the tax (article 82.1 c) of the consolidated text of the Local Finance Act), and any taxpayer is exempt during the first two tax periods of the activity (article 82.1 b)). Declaring your activity code is not the same as paying the tax.

Social Security: the effective date, the contribution base and the mutua

RETA registration is done electronically, and not because the portal happens to be convenient: article 46.1 of Real Decreto 84/1996 says so. You have to report the activity that determines your inclusion (article 46.3), and there is a single registration even if you do several things.

The effective date changed in 2023 and plenty of people still believe registration starts on the 1st of the month. It does not: up to three registrations per calendar year take effect on the day the conditions are met, which is the day you start (article 46.2 a)); from the fourth onwards, on the first day of the calendar month (article 46.2 b)).

Then come two decisions. The first is your contribution base, which you choose within the bracket for your expected net income. In 2026, under Orden PJC/297/2026, the minimum base of bracket 1 of the general table is €950.98 a month, the minimum of the reduced table is €653.59 and the maximum base is €5,101.20. These rates apply on it:

• 28.3% for common contingencies (article 18.2 a)).
• 1.3% for occupational contingencies (article 18.2 b)).
• 0.9% for cessation of activity (article 37.5 a)).
• 0.1% for vocational training (article 37.6).
• 0.9% for the intergenerational equity mechanism (article 18.2 c)).

They add up to 31.5%, and the 2026 self-employed contribution calculator works it out for your bracket.

The second decision is the mutua, the private body that manages your sick pay and work accident cover, and it is the one most people take at random. On registering you have to arrange with a collaborating mutua, jointly, cover for temporary incapacity from common contingencies, for accidents at work and occupational diseases, and for cessation of activity (article 47.1), all compulsory save in the narrow exceptions of article 47.4. The arrangement runs to 31 December and renews automatically unless you give notice before 1 October: choosing badly ties you in for a year.

The reduced start-up contribution: you ask for it when you register, and deregistering kills it

The reduced contribution for starting an activity, which everyone calls the tarifa plana or flat rate, is in article 38 ter of Ley 20/2007, the Self-Employed Workers' Statute. It lasts twelve full calendar months from the effective date of your registration, and during that period you do not contribute for cessation of activity or vocational training. Its amount is not set by that article: the fifth transitional provision of Real Decreto-ley 13/2022 fixed it for 2023 to 2025 and left the following years to each year's Budget Act, which for 2026 was never passed. The amount the social security treasury applies today is in the guide to the 2026 flat rate for new autónomos.

What is settled are the conditions, and they are the ones people break by accident:

• You ask for it when you register. Paragraph 3 requires the request on registration and, for the second period, before that period begins.
• First registration, or two years without one. Three years if you already used the reduction before.
• Deregistering kills it. Paragraph 4 extinguishes the right if you deregister from the RETA during either period.
• The second period is conditional. Another twelve months, only if your annual net income stays below the annual minimum wage, €17,094 in 2026 under Real Decreto 126/2026.
• No adjustment in the first year. Paragraph 6 rules it out: whatever you invoice, there is no later true-up.

With a recognised disability of 33% or more, or as a victim of gender violence or terrorism, the periods become 24 and 36 months (paragraph 10). It does not reach relatives up to the second degree who join the RETA, nor members of institutes of consecrated life (paragraph 11), and hiring employees does not take it away from you (paragraph 7).

Withholding on your invoices and the modelo 130: the decision that confuses people most

The biggest confusion of day one: the income tax withholding on your invoices is not something you choose, it depends on three things that have to be true at the same time.

1. Your activity has to be a professional one. For withholding purposes those are the activities in sections 2 and 3 of the IAE tariffs (article 95.2 a) of the Income Tax Regulation, Real Decreto 439/2007). If your activity code is a business one, your invoices carry no withholding.
2. Your client has to be obliged to withhold. Only legal persons and other entities, and taxpayers carrying on economic activities when they pay in the course of them, withhold (article 76.1). A private individual does not.
3. You have to notify the reduced rate. The general rate is 15%. In the tax period in which you start and the two following ones you may apply 7%, provided you carried on no professional activity at all in the previous year and you notify the payer, who must keep the signed notification (article 95.1). Without it, your client applies 15%.

How that looks on paper is in the guide to your first invoice, and the concept itself in the glossary entry for retención, withholding.

Withholding is tied to the quarterly income tax payment, and hardly anyone tells you so. A professional is not required to file the modelo 130 if in the previous calendar year at least 70% of the income from the activity was subject to withholding (article 109.2). Paragraph 5 adds that, when you are starting out, that 70% is measured over the payment period itself. In plain terms: someone invoicing Spanish companies that withhold can be outside the 130 from the very first quarter; someone invoicing private individuals cannot.

Registering late: what you pay and what you risk

Invoicing before you are registered can be put right, but the expensive part is not the fine. Article 46.2 c) of Real Decreto 84/1996 gives late registrations effect "from the first day of the calendar month in which the conditions for inclusion are met": the month you really started, not the month you applied. And article 35.1.3 finishes the job, stating that the obligation to contribute arises on the day the activity began.

Those months are contributed on the minimum base of bracket 1 of the general table, €950.98 in 2026, with no adjustment (article 308.1.a), rule 5, of the General Social Security Act). At the total rate of 31.5% that is around €299.56 a month if no reduced contribution applies, and it is claimed with whatever surcharges and interest are legally due (article 30). The exact figure comes in the treasury's debt claim, which also reports the late registration to the labour inspectorate.

Two warnings. The penalty drops by 50% if you accept the assessment and pay within the deadline (article 40.3 of the LISOS, the Social Order Offences and Penalties Act). And deregistering late does not mean "effective on the last day of the month": if you do not apply properly and in time, the registration stays alive, contributions keep accruing and that period does not count towards benefits (article 46.4 c)). If what you missed was a tax return, the late filing surcharge calculator and the guide on what to do when you miss a deadline set out the steps.

Foreign nationals and regulated professions: the two cases that skip the general route

If you are not a Spanish national, your tax identification number is your NIE, the foreigner identity number (article 20.1 of Real Decreto 1065/2007). If you do not have one yet, there is a nine-character NIF beginning with the letter M (article 20.2), and the NIF, NIE and IBAN validator checks that yours is correctly formed.

The number is not what entitles you to work. Article 36.1 of Ley Orgánica 4/2000, on the rights and freedoms of foreign nationals in Spain, requires prior administrative authorisation to reside and work from anyone carrying on a gainful activity, whether employed or professional, and paragraph 2 makes the effectiveness of that authorisation conditional on registration with Social Security. Self-employment has its own authorisation, which requires evidence that the investment is sufficient and that jobs may be created (article 37). If the profession requires a qualification, it is conditional on recognition of the degree and, where the law demands it, on joining the professional body (article 36.3). Citizens of the European Union, the European Economic Area and Switzerland need no work authorisation. If your permit only allows employed work, registering is not viable until you change your status first: that is settled at the immigration office, not on the 036. The route is set out on the page for Russian speakers.

If you practise a regulated profession, your first-day decision is a different one: the RETA or your professional body's mutual fund. The eighteenth additional provision of the General Social Security Act, as rewritten by Ley 2/2026 of 29 July and in force since 1 August 2026, includes in the RETA anyone carrying on self-employed work that requires membership of a professional body, unless they opt for their body's mutual fund, provided it was set up before 10 November 1995. And it is a once-only choice: someone who is entitled and does not opt at that moment "may not exercise that option later".

The day after you register: the annual tax return stops being optional

Registering changes something that catches people out: since the 2023 tax year, having been registered in the RETA at any point in the tax period obliges you to file the annual income tax return, with no minimum. That is in the last paragraph of article 96.2 of Ley 35/2006, the Personal Income Tax Act, as drafted by Real Decreto-ley 13/2022. Even if you invoiced three hundred euros, you file.

From there the calendar is predictable. The first weeks sort themselves out if you do this:

1. Keep the filed 036 and your RETA registration document: your bank and your clients' supplier onboarding will ask for them.
2. Set up your ledgers from the first invoice, not in March. How to do it is in the guide on keeping your books.
3. Diarise your quarters: the 2026 and 2027 tax calendar has the dates for the 303, the 130 and the annual return.
4. Set money aside from your first payment: the how much to set aside calculator tells you which part of each invoice is not yours.
5. Record your social security contribution and the rest of your deductible expenses from day one: twelve unrecorded receipts are twelve lost deductions.

One warning: the 036 is not filed once and forgotten. Any change to the details you declared (activity code, address, VAT regime) is reported within one month, unless the rules for the tax set a different deadline, and the census deregistration within one month of ceasing (articles 10.4 and 11.2 of Real Decreto 1065/2007).

kontora records your invoices and expenses, works out the running net income that decides your bracket, warns you of every deadline and produces the draft of each form box by box. Filing at the AEAT and the paperwork at the social security treasury are yours to do.

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