Spain: The Draft SPFE Order Sets UBL as the Only Syntax, Requires a Faithful Copy of Every Privately Exchanged Invoice

KGT Country Update | 15 September 2026 | VAT, e-invoicing and SAF-T monitor

The draft Ministerial Order regulating Spain's public electronic invoicing solution was submitted for public hearing on 17 April 2026 under Royal Decree 238/2026.

It provides that the public solution works exclusively with the EN 16931 semantic model under UBL syntax, that businesses using a private platform must send a faithful copy of every electronic invoice to the tax administration simultaneously with issuance, and that the Order enters into force on 1 October 2026, the event that starts the statutory phase-in clock.

Technical sessions held by the Spanish tax administration for developers set out the resulting calendar: electronic invoicing from 1 October 2027 for businesses above EUR 8 million, 1 October 2028 for the rest, and payment status reporting phased through to 1 October 2029.

Background

Spain's business-to-business electronic invoicing obligation originates in the Crea y Crece Act, Law 18/2022 of 28 September. Royal Decree 238/2026 of 25 March 2026 develops that obligation and amends the invoicing regulations approved by Royal Decree 1619/2012.

The Royal Decree left the technical architecture of the public solution to a Ministerial Order, and it is that Order which fixes the dates: the phase-in periods in Law 18/2022 and in the Royal Decree run from the Order’s entry into force, not from the Royal Decree.

KGT reported in August 2026 that the Crea y Crece clock had not started because the implementing Order remained unpublished. That remains the position.

What has changed is the amount of technical detail now available, from the draft Order and its annexes and from the technical sessions the Spanish tax administration has run for software developers.

The Tax Management Department of the Spanish tax administration under the Ministry of Finance prepared the draft Order. Its executive summary is dated 14 April 2026, and it was put out for public hearing on 17 April 2026. It contains ten articles, one additional provision, one final provision and two annexes.

The Legislative Change

The Order is subordinate legislation made under the third final provision, paragraph 1, of Royal Decree 238/2026, which empowers the Minister of Finance to regulate all technical aspects of the public electronic invoicing solution. It is still a draft. Until it is published, the phase-in periods have not begun, and every calendar date derived from them remains a projection.

Article 3 is the provision with the widest consequences. Electronic invoices issued or interconnected through the public solution must conform to the EN 16931 semantic data model of the European Committee for Standardization under UBL syntax. The technical specifications and volumetrics are not in the Order; they are published separately on the tax administration's electronic office, which means they can change without amending the Order.

Invoices issued or interconnected through the public solution are immediately available to the administration, so no faithful copy is required. An invoice that proves improper because it does not correspond to the documented transaction may be withdrawn, with traceability preserved. Invoices may not carry embedded or integrated files, although interconnected invoices may be sent together with the electronic signature.

Article 4 governs the faithful copy. Businesses obliged to issue and receive electronic invoices who choose not to use the public solution must send an electronic faithful copy to the public solution simultaneously with issuing the invoice.

The copy must carry the information from the original invoice that has an equivalent semantic correspondence and is contemplated in the public solution's syntax, must in all cases meet the minimum content required by Royal Decree 1619/2012, must be identified as a copy in the original-or-copy field of Annex I, and may not carry embedded files.

Article 6 defines the unique code for each invoice as the concatenation of the issuer's tax identification number, the invoice number, the series, and the date of issue, in the defined UBL syntax. Articles 7 and 8 establish the payment communication service, covering rejection, effective payment, collection and non-payment, reported by the recipient and voluntarily by the issuer, again in UBL syntax and with the content and structure set out in Annex II.

Article 9 requires private platforms to retrieve the invoice messages exchanged through the public solution. Article 10 provides for authentication by electronic certificate and, in some cases, by the Cl@ve system. The single additional provision requires the public solution to be available on the tax administration’s electronic office at least two months before its first effective application.

What the Technical Sessions Add

The tax administration has run technical sessions for developers, and the material from the session of 19 May 2026 resolves several points the Order leaves to the electronic office.

The public solution will work exclusively with UBL syntax, identified as ISO 19845. Syntactic validation is straightforward because OASIS publishes an XSD schema. Semantic validation against EN 16931 will be performed using the Schematron model published in the public Connecting Europe repository, which must be updated to the 2026 version of EN 16931.

The 2026 version matters for specific, practical reasons. The 2019 version of EN 16931 cannot represent a number of Spanish national requirements: withholdings, disbursements, reductions, the equivalence surcharge, the special regime for large enterprises at the advanced level, and the requirements for rectifying invoices under Article 15 of the invoicing regulations.

The administration states that the 2026 version of EN 16931, based on UBL 2.5, supports these requirements. This is the correct provenance of the UBL 2.5 reference now circulating: it is a property of the 2026 edition of the European standard, not a figure stated in the draft Order, which refers to UBL syntax without a version.

Two operational statements from the same material deserve emphasis. First, the administration will implement its own high-performance validation solution based on the Schematron, because the declarative Schematron model does not scale to the volumes it expects, which it describes as on the order of thousands of millions of invoices per year.

Second, and more consequentially for implementation planning, no online invoice validation service will be published in production. Senders are expected to run the Schematron themselves before transmitting in order to minimize rejections, on the same basis as the XSD.

The web services will be synchronous and will require authentication by electronic certificate. They will be available in one's own name and under power of attorney; the services for submitting invoices and copies and for changing status will additionally be available in the capacity of social collaborator, but a social collaborator or private platform will not be able to consult or download received invoices or invoice statuses without the corresponding power of attorney.

The administration also states plainly what the public solution is not: it is not an ERP module, not a backup system for a private platform, and not a free cloud invoice storage service.

Timeline

• 28 September 2022  Law 18/2022 (Crea y Crece) establishes the obligation.
• 25 March 2026 Royal Decree 238/2026 develops the system; published in the Official State Gazette on 31 March 2026.
• 14 April 2026 executive summary of the draft Ministerial Order.
• 17 April 2026 draft Order submitted for public hearing and information.
• 19 May 2026 tax administration technical session for developers on the obligation and the public solution.
• 10 September 2026: further tax administration developer session, "Update on the Public Electronic Invoicing Solution".
• 1 October 2026 entry into force of the Order, which starts the statutory phase-in clock. Projected, since the Order remains a draft.
• 1 October 2027 electronic invoicing for businesses with turnover above EUR 8 million; payment reporting for the same group.
• 1 October 2028 electronic invoicing for all other businesses and professionals; payment reporting for small and medium-sized legal persons at or below EUR 8 million.
• 1 October 2029 payment reporting for small and medium-sized income-attribution entities and natural persons at or below EUR 8 million.

Businesses Affected

Every business and professional within the scope of Article 3 of Royal Decree 238/2026, subject to the exceptions in Article 4 and the second additional provision of that decree. For multinationals the significant group is those above EUR 8 million turnover, whose obligation is projected to begin on 1 October 2027, with payment status reporting beginning on the same date rather than later.

The distinction between the invoicing and payment obligations is worth stating carefully, because commentary has blurred it. For large businesses both start together on 1 October 2027. For smaller businesses, invoicing starts on 1 October 2028 while payment reporting is split: legal persons from 1 October 2028, but income-attribution entities and natural persons only from 1 October 2029. The 2029 date applies to payment reporting, not to an electronic invoicing obligation.

Required Actions

• Plan for UBL only. The public solution does not accept CII, EDIFACT or Facturae. A group standardising on CII for France and Germany will need a UBL output for Spain.
• Plan for EN 16931 in its 2026 edition, based on UBL 2.5, because the 2019 edition cannot carry Spanish withholdings, disbursements, reductions, the equivalence surcharge or the rectifying invoice requirements.
• Build Schematron validation into the outbound process before transmission. There will be no production validation service to call, so an invoice that fails validation fails at the point of submission.
• If using a private platform, design the faithful copy as a simultaneous obligation, not a batch one. The copy must go to the public solution at the moment the invoice is issued, must be flagged as a copy in the original-or-copy field, and must carry no embedded files.
• Remove embedded attachments from Spanish electronic invoices. Neither invoices nor faithful copies may carry embedded or integrated files.
• Implement the unique code as the concatenation of issuer tax identification number, number, series and issue date, and ensure invoice numbering and series are stable enough to support it.
• Scope the payment status reporting as a separate obligation from invoicing. It requires rejection, payment, collection and non-payment messages, and for large businesses it starts on the same date as invoicing rather than later.
• Resolve powers of attorney early. A private platform or social collaborator cannot consult or download received invoices or statuses without one, which affects any outsourced accounts payable arrangement.
• Treat every calendar date as provisional until the Order is published. The entire phase-in runs from entry into force.

Practical Implications

The most underestimated requirement is the faithful copy. A business using a private platform does not merely exchange invoices with its counterparty; it must simultaneously lodge a structured copy with the tax administration. That is a second transmission path, with its own validation, its own failure modes and its own volumetric limits, and it applies to every invoice. Existing Peppol connectivity does not remove this work, because the faithful copy is a Spain-specific flow to a Spanish endpoint.

The second is the absence of a production validation service. Many jurisdictions provide one, and implementation plans routinely assume it. Spain has said it will not. This moves the validation burden decisively into the sending system and makes pre-transmission Schematron execution a design requirement rather than an optional control.

The third is the syntax decision. Spain has chosen UBL exclusively, while France operates a multi-syntax regime and Germany is built around hybrid formats. A group that assumed a single European output format will need to maintain at least two, and the Spanish one must track the 2026 edition of EN 16931 rather than the 2019 edition that most existing implementations are built to.

Finally, the clock has still not started. Two weeks before the projected entry into force of 1 October 2026, the Order remains a draft. Every date in this update derived from that entry into force is a projection, and if publication slips, the entire phase-in slips with it. That is a planning advantage as much as a risk: the lead time to 1 October 2027 is unlikely to shorten, and it may lengthen.

Expected Next Steps

Publication of the Ministerial Order in the Official State Gazette is the event to watch, because it starts the phase-in and fixes the calendar. The technical specifications and volumetrics will be published and maintained separately on the tax administration's electronic office, and the Schematron will need to be updated to the 2026 edition of EN 16931.

The tax administration is continuing its developer session program. KGT will report the Order when it is published and will confirm the resulting dates.

How Can KGT Support You?

KGT delivers SAP-integrated electronic invoicing and statutory reporting. For Spain, we produce EN 16931 compliant UBL from SAP billing data, implement the faithful copy as a simultaneous parallel transmission where a private platform is used, embed Schematron validation ahead of transmission so that failures surface before submission rather than after, and build the payment status reporting as a distinct message flow from the invoice flow.

We also help clients reconcile Spain against the rest of their European footprint, which in practice means deciding where a single output can serve several jurisdictions and where, as with the Spanish UBL-only requirement and the 2026 edition of EN 16931, it cannot. For clients on SAP Document and Reporting Compliance we support scoping, country activation and testing, and we give an even-handed view of where an add-on is the better answer.

This country update is provided for general information only and does not constitute tax, legal or professional advice.