Starting as self-employed involves more than completing a form. You need to describe your activity, prepare your documents and coordinate registration with the tax authority and the relevant Social Security registration. Each procedure serves a different purpose; confirmation of one does not prove that the other has been completed.
This guide helps you prepare your application before starting, particularly if this is your first business activity in Spain. The aim is to submit consistent information and know what to check afterwards. Businesses do not all have the same obligations: selling products, providing services or keeping another job may change what needs to be reviewed.
Define your activity and when it will begin
Describe in plain language what you will sell or which services you will provide, to whom and from where. The AEAT states that tax registration must be submitted before activities or operations begin. Do not therefore use the date of your first invoice as your only reference: also explain whether you have already commissioned work, rented premises or planned purchases for the business. [1] [3]
For example, someone providing services from home and someone opening a shop need to review different details, even though both are self-employed. Prepare a realistic timeline of preparations, the intended start and initial assignments. If you have already started, explain what actually happened; do not try to resolve it by choosing a fictitious date or submitting another registration without reviewing your position.
- Note your main activity and any other activities you plan to carry out.
- Distinguish the intended start date from earlier preparations.
Gather your details before opening the forms
Prepare your identification, contact details and tax and business addresses. For self-employed registration, Importass asks for information including IAE and CNAE activity codes, the start date, estimated net earnings and a bank account. Gather these details in one record and check that names and identification numbers match across the documents. [2]
Add a short explanation of your circumstances: whether you also have a job, were registered previously or will carry out several activities. Bring documents that clarify these points, without assuming everyone needs the same paperwork. If somebody else will submit the application, agree how their authority to represent you will be established. Preparation also means checking that you can access the procedure and receive its communications.
- Keep identification, address and contact information in an updated record.
- Prepare the IBAN and check account ownership or the relevant authorisation.
Review form 036 and your tax obligations
Form 036 is used to register, amend details or deregister in the register of businesses, professionals and withholding agents. When preparing to start, review the activity being declared and the tax details relevant to your case. Registration information can communicate VAT, IRPF income tax or withholding circumstances; selecting every obligation as a precaution or copying another self-employed person is not appropriate. [1] [3]
The AEAT electronic office allows you to consult registered tax details and submitted declarations. If you have been in business before, this helps identify information that needs checking before another notification is sent. Once the form has been submitted, save the copy and confirmation. Check the details actually submitted, especially activity, address and dates, rather than keeping only the draft used during preparation. [1]
- Ask which returns will apply to your activity and why.
- Keep drafts separate from copies of forms actually submitted.
Coordinate RETA registration with Social Security
RETA is the Spanish Social Security scheme for self-employed workers. The Importass registration service says you must apply before starting your activity. The process reviews your activity, estimated net earnings, contribution base, mutual insurance provider and any applicable benefits. Do not assume that submitting form 036 also completes this procedure. [2]
Base your estimate on business information and explain any uncertainties; net earnings are not simply the amount you expect to invoice. Importass requires an account for contribution payments and provides for authorisation when the account belongs to someone else. Before confirming, compare the details with your tax registration preparation. Coordinating dates means reviewing each situation, rather than automatically entering the same date in every field. [2]
- Check the activity, start date and banking details before confirming.
- Keep the outcome of the procedure and check that registration is recorded.
Complete the file and prepare for ongoing administration
Organise a folder containing submissions, confirmations and a record of decisions made. Note which documents you will provide for tax returns and who will review each obligation. If you ask a gestoría to arrange registration, clarify whether the quote covers only the initial procedure or also bookkeeping support and subsequent returns. This avoids confusing a single procedure with ongoing administration.
If you find a difference between what was planned and what was submitted, first review the confirmation and the position recorded by each authority. The AEAT provides facilities to consult and amend tax registration details; Importass provides self-employed registration and information about it. Do not repeat applications to correct an error without first identifying the appropriate notification. The final goal is to know what was submitted, with which details and what remains outstanding. [1] [2]
- Agree how invoices, supporting documents and activity changes will be provided.
- Keep a list of outstanding tasks and documents received.
Frequently asked questions
Does tax registration include Social Security registration?
They are separate procedures. Form 036 provides tax registration information to the AEAT; self-employed registration is handled by Social Security. Check both confirmations and the recorded status, without assuming that one submission automatically completes the other.
What if I do not yet know how much I will earn?
Prepare a reasoned estimate using the information available and explain what remains uncertain. Importass requests estimated net earnings for registration. Do not confuse income, invoicing and net earnings: review how to calculate them for your activity before confirming your details.
Can I prepare my registration if some documents are missing?
You can organise the information and identify what is missing. Before submitting, check that the required details are complete and the dates reflect your actual circumstances. If you have already started working, say so, so that the appropriate procedure can be reviewed.