Registering with the Tax Agency to start practising: form 036, its deadlines and the end of form 037

Starting to practise on your own account requires several formalities: registering with the bar as a practising member, registering with the Social Security regime or the relevant mutual society, and registering in the Tax Agency's census of businesspeople, professionals and withholding agents. The latter is done with form 036.

A single form since February 2025

For years two forms coexisted: 036 and 037, a simplified version. According to the Tax Agency, Order HAC/1526/2024 abolished form 037, with effect from 3 February 2025. Since then, the simplified function that 037 offered is provided through form 036 itself.

For a lawyer starting out, that simplifies the choice: there is no alternative form.

The deadlines

Registration, before the first engagement

The key rule is the registration one: it must be filed before starting the activity. In practice, it is wise to do it before issuing the first invoice or signing the first engagement letter with a client.

Registration is also the moment when, where applicable, the obligation to withhold or make payments on account arises. For a lawyer who hires an employee or rents premises, that point is relevant.

Amendments

Any change in the declared data must be reported within one month of the day after the change. For a lawyer, typical changes are moving the activity's address, opening a new office or starting a different activity.

Deregistration

When you stop practising on your own account, for example on joining a firm as an employed lawyer or on retiring, you have one month from the cessation to file the deregistration.

Other formalities with the same form

According to the Tax Agency, form 036 also serves for other formalities, each with its own deadline, such as applying for the tax identification number, registering in the monthly VAT refund register or opting for certain regimes and VAT-related communications.

Mistakes to avoid

• Starting to invoice before registering. The registration deadline is before the start of the activity, not after.
• Forgetting to report changes. A move of office or a new activity has one month to be reported.
• Not deregistering the activity on ceasing to practise on your own account, which keeps alive obligations that no longer apply.

What comes after registration

Census registration is the starting point of the lawyer's periodic tax obligations:

• Quarterly VAT, with form 303, which we explain in the guide to VAT for self-employed lawyers.
• Income tax instalment payments, with form 130, unless the conditions for not filing it are met, as we explain in the guide to form 130.
• Record books, mandatory for professionals under direct estimation, which we review in the guide to the record books of the self-employed lawyer.

Checklist for getting started

1. Register with the bar as a practising member at the relevant bar association.
2. Settle the welfare regime: Social Security or the alternative mutual society.
3. File form 036 before the first professional action.
4. Set up invoicing and the record books from day one.
5. Note in the calendar the quarterly deadlines and the one-month period to report any change.

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