Form 037: The Simplified Census Return and When It Makes Sense to Use It

Whenever a freelancer or small business changes something about its activity, the Spanish Tax Agency (AEAT) needs to know. That notice is made through the census return, and this is where a common question arises: Form 036 or Form 037? Understanding the difference saves you time and, above all, spares you unpleasant tax notices.

What Form 037 is and how it differs from Form 036

Form 037 is the simplified census return. It is used to notify the AEAT of registration, changes or deregistration in the Census of Entrepreneurs, Professionals and Withholding Agents, just like Form 036, but with fewer sections and a much shorter form. Its purpose is to make the most common filings easier for individuals who don’t need to report complex situations.

Form 036 is the full version: it accepts every kind of taxpayer, including companies, and covers more special cases (particular VAT regimes, intra-EU transactions, groups, representatives, etc.). Form 037, by contrast, is designed for individuals in straightforward situations. In practice, it is the fast track when your case is a textbook one.

One important limit is worth remembering: Form 037 has restrictions on use. If your situation includes anything outside its scope, the AEAT online portal or the official instructions will direct you to Form 036. Before filing, always check on the AEAT portal that your case is eligible; it is the authoritative source, because the criteria are updated over time.

When it is used and which filings it covers

The typical uses are those of a freelancer starting or closing an activity: registering in the census, reporting a change of tax address or contact details, changing the activity’s tax heading, or giving notice of deregistration. It can also be used to adjust the filing frequency or the tax regime when the situation allows it.

There are three ideas worth keeping clear:

First, the census return is not a stand-alone filing. What you state in it determines the obligations the AEAT will later require of you: if you are registered as required to file quarterly VAT, withholdings or instalment payments, those forms will be demanded of you even if you have no activity. An outdated census record leads to notices and penalties for forms not filed.

Second, deadlines matter. Registrations, changes and deregistrations must be reported within the deadlines set by law; don’t wait for the next tax settlement to bring your census record up to date. Check on the portal the deadline that applies to your specific case.

Third, filing is done online. It is normally done through the AEAT online portal with a digital certificate, Cl@ve or other accepted identification methods, and you should always keep the filing receipt.

What this means for your business

Beyond the form itself, the practical decision is this: review your census record now, not when a notice arrives. These are the points we recommend checking:

If you are about to start an activity, decide before filing the registration which tax heading, which personal income tax (IRPF) regime (simplified direct estimation or another) and which VAT treatment fit your business. A mistake at the outset carries through to withholdings, instalment payments and incorrectly issued invoices.

If you have changed address or activity, or have stopped working, report it and check that your periodic obligations match your actual situation. Deregistering an activity without updating the rest of your details can leave you with live obligations that no longer apply to you.

If you have a company, Form 037 is not for you: your route is Form 036. And if you are a freelancer with more complex operations, such as purchases or sales to other EU countries or rentals subject to withholding, the prudent course is not to assume the simplified form is enough. Check what your case requires.

Finally, keep the receipt for every filing and, after a while, check that your census status reflects what you declared. A filing that has been submitted but not verified is a common source of surprises.

At Zythos Business we handle the accounting and tax affairs of freelancers and SMEs, and checking that the census record matches each client’s reality is part of our regular work: which forms apply to them, when, and why. If you are unsure whether your census status is up to date, we can review it with you before the tax authorities do.