Do you need to register as self-employed (autónomo)?

Key rules

• Registration test: Habitual, personal activity done for profit on your own account must be registered.
• Occasional income: Truly occasional income does not need registration, but regular, organised income does, on any platform.
• Low income: Earning under the minimum wage does not exempt you from registering.
• Unregistered work: Working unregistered risks back contributions with a surcharge and interest, plus a fine.

The short answer

You must register as self-employed if you carry out an activity habitually, personally and for profit, on your own account. Truly occasional income does not need registration. Anything in between is judged case by case, and working unregistered when you should be registered risks penalties.

The three-part test

You are likely to need registration if all of these are true:

• You do the work yourself. You carry out the activity personally and directly. Owning a business or investing in one, without working in it, is different.
• It continues over time. A one-off job is not habitual. Regular clients, repeat sales or ongoing income are.
• You do it to earn a profit. You act on your own account, not as an employee.

The test applies to anyone aged 16 or over, of any nationality. It applies whether or not you employ other people.

Does low income let you skip registration?

No. Earning less than the minimum wage (SMI) does not exempt you. Earning more does not prove you are self-employed either. Social Security looks at the real facts: how regular the activity is, how organised it is, and what kind of activity it is.

Platforms and side income

• Selling your own used things on a resale app is generally not self-employment.
• Regular resale, freelance gig work or content creation with continuing income is treated as habitual activity, whatever the platform.
• Platforms report seller income to the tax agency (AEAT), so your sales are more visible than you might expect.
• Tax can apply even when registration does not. Not needing to register as autónomo does not mean the income is tax-free.

If your case is borderline

Ask the Social Security office (TGSS) for its view before you start. Each case is decided individually, so a written answer for your situation is worth more than a general rule.

What happens if you work unregistered

Social Security can register you itself and charge the unpaid contributions, with a surcharge and interest. The Labour Inspectorate can also fine you. Registering late can also cost you the reduced-fee schemes for new self-employed workers. If you meet the test, register before you start working.

The decision tool, checklist, warnings and questions below help you apply this to your own case.

Choosing between options

Do you need to register as self-employed?

• Register as self-employed: Your income is regular, organised and for profit, for example regular resale, freelance gig work or content creation with continuing income.

• No registration needed: Your income is truly occasional, or you only sell your own second-hand personal items. Tax obligations can still apply.

• Ask the Social Security office first: Your situation is borderline and you cannot tell whether it counts as habitual.

You must register if you habitually, personally and directly carry out an activity for profit on your own account. Your income level alone does not decide it.

Checklist

• Check whether you carry out the activity yourself, personally and directly, rather than only owning or investing in it.

• Check whether the activity continues over time rather than being a one-off job.

• Check whether you do it to earn a profit, on your own account.

• Look at how organised the activity is, for example regular clients, repeat sales or ongoing content income.

• Do not rely on your income being below the minimum wage (SMI) to skip registration, because it does not exempt you on its own.

• If your case is borderline, ask the TGSS (Social Security office) for its view before you start, since each case is judged individually.

• If you meet the test, register before unregistered work leads to back contributions, a surcharge and a possible fine.

What to watch out for

• Back contributions, surcharge and interest: If you work without registering, Social Security can register you itself and charge the unpaid contributions with a surcharge and interest. Register as soon as you meet the test, and ask the Social Security office if you are unsure. Register as soon as your activity meets the test, and ask the Social Security office if you are unsure.

• Fine from the Labour Inspectorate: The Labour Inspectorate can fine you for working without registration. Fines are graded minor, serious or very serious, depending on the circumstances. Do not start regular paid work until you are registered. Register before you begin regular paid work.

• Losing the reduced-fee schemes: Registering late loses the benefit of the reduced-fee schemes. Register on time so you can use them. Register on time to keep access to the reduced fees.

Check the current penalty levels with the TGSS, Spain's Social Security office, before acting.

Frequently asked questions

Do I need to register if I only sell my old things on a resale app?

No, selling only your own second-hand personal items on a resale app is generally not treated as self-employment. It changes if you buy to resell or sell regularly for profit. Tax obligations can still apply even when Social Security registration does not.

Does earning less than the minimum wage mean I can skip registration?

No, earning less than the minimum wage (SMI) does not by itself exempt you from registration. Earning more does not automatically prove your activity is habitual either. Officials look at the real facts, such as how continuous and organised your work is.

Will the tax agency know about my sales on online platforms?

Yes, platforms now report seller income to the AEAT, Spain's tax agency, under EU rules. This means more scrutiny of regular sellers. If your sales are regular, get your situation checked before the tax agency asks.

What happens if I work for a while without registering?

Social Security can register you automatically and charge the unpaid contributions with a surcharge and interest. The Labour Inspectorate can also fine you, with the amount depending on how serious the case is. You also lose access to the reduced-fee schemes if you register late.