Following the Royal Decree 238/2026 recently published on March 25th, the Spanish Government has now released on April 17th a draft Ministerial Order [↗︎] that specifically describes how the “Public Solution” intends to operate under the mandate. Overall, it appears very similar to how the French B2B e-invoicing mandate was initially designed.
According to the draft, companies would be able to use a Public Solution either for the full issuance and transmission of e-invoices or for transmission only. The system would be accessible through both an API and a web portal.
Alternatively, businesses could use Private Platforms to exchange electronic invoices, in which case a faithful copy of the invoice exchanged between platforms would still need to be transmitted to the Public Solution.
This draft Ministerial Order intends to clarify the technical and functional e-invoicing specifications for the Public Solution to be implemented in 2027 and 2028, and is open to public consultation until May 6th, 2026. It represents one of the last opportunity to provide feedback on how the Public solution will operate
Timeline implementation adjustments
Based on the current draft, the Ministerial Order is set to enter into force on October 1st, 2026, which would trigger the following legal countdown for compliance:
- Large Companies (Turnover > €8M): should be fully compliant by October 1st, 2027 (12 months after entry into force).
- Smaller Businesses and Independent Professionals: should comply by October 1st, 2028 (24 months after entry into force).
A specific relief period would be granted to self-employed individuals with an annual turnover under €8M. While they should begin issuing and receiving e-invoices by October 1st, 2028, they would only be required to transmit invoice statuses (payment/rejection) starting October 1st, 2029.
Content and technical requirements regarding e-invoice issuance and transmission
The first section of the draft Ministerial Order provides technical requirement regarding how data must be structured and exchanged through the Spanish e-invoicing model, depending notably on the issuance situation.
- Standardizing the public flow format (article 3): all e-invoices shared using the Public Solution should use the UBL syntax (under the EN16931 standard), contain a digital signature and requirements strictly prohibit attachment files (like PDFs).
Additionally, data content, set out by Annex 1 of the draft Ministerial Order [↗︎], would depend on the issuance method chosen by businesses: invoices manually generated via the public portal would be limited to basic legal fields, whereas those issued from a business’s own software and transmitted via the Public Solution could include extended business data. - The “Faithful Copy” requirement (article 4): for e-invoices exchanged between private platforms, a “faithful electronic copy” would need to be created and transmitted in real-time to the Public Solution in UBL syntax
- Technical control of e-invoices (article 5): Whether issued via the Web Portal or transmitted via Web Services (API), the Public Solution would automatically control all e-invoices, including faithful copies. It would return an “Admitted” status (“Admitida”) with a verification code or a “Rejected” status (“Rechazada”) detailing errors, with 4 calendar days to fix those.
- Unique Invoice Identification (article 6): To ensure the uniqueness of each issued e-invoice, the draft order provides that a unique invoice identifier will be generated by combining several data elements: the issuer’s tax identification number (NIF), the invoice series and number, and the issue date.
E-invoice lifecycle information and reporting methods
The second part of the draft provides details regarding e-invoice lifecycle information to be shared and the reporting methods allowed.
- Invoice Statuses to be reported, and format (article 7): all invoice lifecycle statuses issued and transmitted will have to follow the UBL syntax (specified in Annex II [↗︎]) and be transmitted through the Public solution.
First, the recipient of the e-invoice would be required to report the commercial rejection of an invoice, the final effective payment date, and the payment deadline. He may also report the receipt date of goods/services or of the invoice to clarify timelines under the Spanish Late Payment Law.
Conversely, the issuer could report information regarding collection, non-payment, or discrepancies with the buyer’s data.
- How to report statuses (article 8): statuses of e-invoices, including mandatory payment data reporting, could be transmitted either manually via the Web Portal or automatically through Web Services (API), independently of the e-invoice issuance and transmission methods.
The draft order also provides information regarding invoice reception service from the Public solution (article 9) and the authentication, identification and representation methods for accessing the Public solution (article 10).
