Mandatory e-invoicing: the clock is already running for self-employed lawyers since 6 October

The BOE of 5 October 2026 published Order HAC/1028/2026 of 2 October, regulating the public e-invoicing solution. It looks like a technical rule, but it has an immediate practical consequence: its entry into force, on 6 October 2026, is the date from which the deadlines for mandatory e-invoicing between businesspeople and professionals are counted.

The system is regulated by Royal Decree 238/2026 of 25 March, published in BOE no. 79 of 31 March 2026. Its fourth final provision sets no calendar dates, but periods counted from the entry into force of the order. With the order now published, the Tax Agency has translated those periods into specific dates.

Who it affects

Under Article 3 of Royal Decree 238/2026, the invoice must be issued in electronic format when the recipient is a businessperson or professional with a seat, permanent establishment or domicile in Spain. Professionals are included in the same regime as businesspeople, as the Tax Agency's information note recalls.

For a self-employed lawyer, that means the obligation affects invoices issued to companies and other professionals. The royal decree contains no rule for transactions with consumers: its scope is limited to transactions between businesspeople and professionals. Article 4 also excludes simplified invoices, except qualified ones.

The timetable

A lawyer who practises on their own and does not exceed 8 million euros in turnover is in the second group: issuing and receiving e-invoices from 6 October 2028. Reporting invoice statuses, such as payment, is postponed one more year for them, because the royal decree makes it voluntary for individuals during the first twelve months.

The free public solution

The order regulates a Tax Agency tool designed, according to its text, especially for small and medium-sized companies and professionals. Its main features are:

• Free: the order's preamble says access and its uses are free of charge for users.
• Access: through the Tax Agency's electronic office, with an electronic certificate, and also with Cl@ve for the issuing form, status reporting and queries.
• Issuing: through a web form, invoice by invoice, or through web services.
• Format: invoices follow the European semantic model EN 16931 with UBL syntax.
• Representatives: whoever acts on behalf of the obliged party, such as an adviser, must be authorised in the Tax Agency's register of powers of representation.

Use of the public solution is optional. Those who prefer a private platform can use it, but that platform must send the public solution a copy of each invoice issued.

What changes day to day

The royal decree does not just change the format. It also obliges the recipient to inform the issuer of acceptance or rejection of the invoice and of full effective payment, within four calendar days, excluding Saturdays, Sundays and national holidays (Article 10). That payment information also reaches the public solution (Article 12).

For those above 8 million euros, the royal decree also provides that, during their first twelve months of obligation, invoices are accompanied by a PDF that guarantees legibility.

Relation to Verifactu

E-invoicing between professionals is not the same as Verifactu, the regulation on invoicing computer systems, which has its own timetable. We explain it in the Verifactu guide for self-employed lawyers. It is wise to choose invoicing software that handles both obligations.

What to do now

1. Work out what share of invoicing goes to companies and professionals and what share to private individuals.
2. Ask the invoicing software provider whether it will issue in UBL format and how it will connect to the public solution.
3. Try the public solution when available: the order requires it to be available at least two months before its first effective application.
4. Review the authorisation of the adviser who handles the invoices.

If you also file quarterly VAT with form 303, e-invoicing does not change the tax, but it does change how it is documented. More guides in Solo and small-firm lawyers.