By Velnor Capital Team • • 8 min read
Every year, thousands of Spanish self-employed professionals and small businesses face the same stressful situation: February arrives, and they realise they have not properly tracked their transactions with clients and suppliers throughout the year. Form 347 — the Annual Declaration of Transactions with Third Parties — catches many off guard. According to data from the Agencia Tributaria (AEAT), over 3.2 million taxpayers filed this declaration in 2024, and penalties for late or incorrect filing start at €200 and can exceed €20,000 depending on the volume of unreported transactions. For self-employed professionals (autónomos) working with multiple clients or suppliers, the risk of errors is especially high.
Form 347 is rooted in Spanish tax law, specifically in Royal Decree 1065/2007, which regulates tax management and inspection procedures. Its legal purpose is straightforward: Hacienda wants a cross-referenced view of commercial transactions between taxpayers. When you declare €50,000 in sales to a client and that client declares €50,000 in purchases from you, the figures must match. If they do not, AEAT's automated systems flag the discrepancy — and an inspection notice may follow. Understanding the legal framework is not optional for autónomos in 2026; it is a fundamental part of staying compliant and avoiding unnecessary fines.
In this guide, you will learn exactly what Form 347 is, who must file it, what the €3,005.06 threshold means and how it applies, how to fill in each section correctly, and what the filing deadline is for 2026. You will also find a practical example with real numbers, a table of the most common mistakes, and the documentation you need to gather before you start. Whether you are a freelancer, a sole trader, or a small business owner, this article gives you the complete picture — for informational purposes only, as always. Consult a qualified tax advisor for advice tailored to your specific situation.
Form 347 (Modelo 347) is the Annual Declaration of Transactions with Third Parties (Declaración Anual de Operaciones con Terceros). It must be filed once a year and covers all commercial transactions carried out during the previous calendar year with any single client or supplier whose total annual amount — including VAT — equals or exceeds €3,005.06.
This threshold is one of the most misunderstood aspects of the form. The €3,005.06 figure is not arbitrary: it is the peseta-era equivalent of 500,000 pesetas, converted to euros and never updated. It applies per counterparty, per year, and it includes VAT. That means if you invoiced a single client €2,500 + €525 VAT (21%) = €3,025 total, that client must appear on your Form 347.
The declaration is bidirectional and cross-checked. AEAT uses it to verify that the amounts declared by both parties in a transaction are consistent. If your client declares €10,000 in purchases from you but you only declare €8,000 in sales to them, the system will detect the mismatch. This cross-referencing is why accuracy matters far more than many autónomos realise.
It is also worth noting that Form 347 does not generate a tax payment. It is purely informational — but the consequences of filing it incorrectly or not filing at all can be very costly.
Understanding how to correctly invoice as a self-employed professional is the foundation for completing Form 347 accurately, since every transaction you report must be backed by a valid invoice.
Any autónomo who has carried out transactions with a single client or supplier totalling €3,005.06 or more (VAT included) during 2025 must file Form 347 in February 2026. This applies regardless of your tax regime — whether you are on direct estimation (estimación directa) or objective estimation (módulos).
SMEs and limited companies (SLs, SAs) with commercial relationships exceeding the threshold with any counterparty must also file. For businesses with many suppliers or clients, this can mean hundreds of entries on a single form.
Homeowners' associations must declare payments to providers — such as cleaning companies, maintenance services, or insurers — if those exceed €3,005.06 annually.
Insurance entities must declare premiums collected from policyholders when they exceed the threshold per policyholder.
Government bodies, local councils, and public entities are required to file, often with significant volumes of data covering procurement and service contracts.
Certain taxpayers and transaction types are excluded:
If you are unsure whether your transactions with a specific counterparty need to be declared, your safest option is to include them — and consult a tax advisor.
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Start for free →| Concept | Why it does NOT apply or is incorrect |
|---|---|
| "I only include net amounts, without VAT" | The €3,005.06 threshold and reported amounts must include VAT |
| "I don't need to declare cash transactions" | Cash transactions above the threshold must be declared separately in box 1 of the form |
| "Transactions with the same NIF in different quarters cancel out" | All transactions with the same counterparty accumulate across the full year |
| "If my client files it, I don't have to" | Both parties must file independently — it is not a shared declaration |
| "I'm on módulos, so I'm exempt" | Autónomos on objective estimation must still file if they exceed the threshold |
| "Returns and discounts reduce the threshold automatically" | Corrective invoices (facturas rectificativas) must be declared in the quarter they were issued, not offset against the original |
| "The deadline is March, like always" | In 2026, the filing deadline is 28 February 2026 for the 2025 fiscal year |
| "I don't need to file if I only have one client" | The number of clients is irrelevant — the threshold applies per counterparty |
Before you open the AEAT electronic portal or your accounting software, gather the following:
If you have been properly tracking your deductible expenses and VAT throughout the year, much of this data will already be organised. Good bookkeeping in real time is the single biggest time-saver at this point of the year.
The following example illustrates a self-employed graphic designer (autónomo) with three main clients during 2025:
| Counterparty | NIF | Q1 (€ incl. VAT) | Q2 (€ incl. VAT) | Q3 (€ incl. VAT) | Q4 (€ incl. VAT) | Annual Total | Include in 347? |
|---|---|---|---|---|---|---|---|
| Marketing Agency S.L. | B12345678 | €1,210 | €1,452 | €1,210 | €968 | €4,840 | ✅ Yes |
| Tech Startup S.L. | B87654321 | €605 | €726 | €0 | €484 | €1,815 | ❌ No (below threshold) |
| Retail Group S.A. | A11223344 | €3,025 | €2,420 | €3,630 | €1,815 | €10,890 | ✅ Yes |
| Freelance Photographer | 12345678Z | €0 | €0 | €1,210 | €1,936 | €3,146 | ✅ Yes |
For the entries that must be declared (Marketing Agency, Retail Group, and the freelance photographer), the form requires:
The form is filed electronically through the AEAT website using a digital certificate (certificado digital), Cl@ve PIN, or via authorised software. There is no paper option for most taxpayers.
For context, if you have been correctly filing your quarterly VAT returns using Form 303, your quarterly subtotals should align closely with what you report in Form 347 — making the reconciliation process considerably easier.
The filing window for Form 347 covering fiscal year 2025 is:
This is a firm deadline. There are no extensions, and the form cannot be filed after 28 February without incurring penalties. Late filing penalties under Article 198 of the General Tax Law (Ley General Tributaria) are as follows:
If you discover an error after filing, you can submit a supplementary declaration (declaración complementaria) to add omitted data, or a substitutive declaration (declaración sustitutiva) to replace the entire filing. Both carry their own penalty implications, so it is better to get it right the first time.
Manually cross-referencing every invoice by client, calculating quarterly subtotals, and verifying NIF numbers is time-consuming and error-prone. In 2026, autónomos have no excuse for doing this entirely by hand — digital tools can automate much of the process.
The key is having accounting software that automatically tags each invoice by counterparty and accumulates totals in real time. When February arrives, the data is already organised and ready to export or transfer to the AEAT portal. This also makes it much easier to reconcile your Form 347 data with your quarterly VAT filings and your IRPF withholding records.
Velnor Capital (from €19.99/month) is designed precisely for this type of workflow. It helps self-employed professionals and SMEs track income and expenses by counterparty throughout the year, so that preparing Form 347 becomes a matter of minutes rather than days of manual reconciliation.
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Official source: Agencia Tributaria — AEAT (Spanish Tax Agency). The information in this article is for informational purposes only. Always consult a tax advisor for your specific situation.
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Try 7 days free →Official source: Agencia Tributaria — AEAT (Spanish Tax Agency). The information in this article is for informational purposes only and is updated in accordance with current regulations. Always consult a tax advisor for your specific situation.
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