Spain’s e-invoicing mandate, for developers
Spain is moving toward mandatory structured e-invoicing on two parallel tracks. B2G e-invoicing has been mandatory since 2015 through the FACe general entry point, using the Spanish Facturae XML format. B2B e-invoicing becomes mandatory under the Ley Crea y Crece (Law 18/2022) — phased in from the date its implementing regulation (Reglamento) takes effect, which is still pending; once published, large companies (turnover above €8M) are expected to follow roughly one year later and all other businesses roughly two years later.
Separately, the Veri*Factu regime (Royal Decree 1007/2023) sets anti-fraud requirements for invoicing software — tamper-evident records, hash chaining, and a QR code — with optional real-time reporting to the AEAT. It applies to billing systems, not to the invoice exchange itself, and is a distinct obligation from the B2B mandate.
What the B2B mandate will require
- Structured electronic invoices between businesses (not PDF-only).
- A dual model: a public solution operated by the tax authority plus private platforms that must report invoice status and copies to the public solution.
- Accepted syntaxes expected to include Facturae, UBL, CII (EN 16931-based) and EDIFACT — each carrying the EN 16931 semantic core.
- Mandatory invoice-status messaging (accepted / rejected / paid).
What Veri*Factu requires (separate track)
- Invoicing software must produce immutable, hash-chained billing records with a QR code and a “Veri*Factu” / “no Veri*Factu” marking.
- Software vendors had to adapt; corporate-tax-paying businesses are in scope first, self-employed individuals later.
- It governs the software that issues the invoice, not which platform receives it.
Where Slipstack fits
What Slipstack does: generates EN 16931-compliant structured invoices over a JSON API — Factur-X / CII (PDF + embedded XML) and standalone UBL — plus a free EN 16931-core validator. If your Spanish integration accepts EN 16931 UBL or CII (formats the B2B mandate is expected to permit), Slipstack produces the structured document you build on. Validate the core rules for free with the EN 16931 / XRechnung core validator.
What Slipstack does not do: it does not generate the Spanish Facturae XML required for B2G via FACe; it is not a Veri*Factu-certified billing system and does not produce hash-chained Veri*Factu records or the AEAT QR; and it does not connect to FACe, the AEAT public solution, or any private platform — submission and status reporting go through your chosen provider. Use Slipstack to generate and validate the EN 16931 core; route, sign, and report through a Spanish-certified platform. For what a mandated routing platform is, see what is a PDP.
Frequently asked questions
Is B2B e-invoicing mandatory in Spain yet?
Not yet in force. The Ley Crea y Crece mandate begins phasing in once its implementing regulation takes effect — large companies first (~1 year after publication), all others ~2 years after. Dates depend on that regulation.
Does Slipstack generate Facturae?
No. Slipstack generates EN 16931-compliant Factur-X / CII and UBL. Facturae is a separate Spanish format required for B2G via FACe; Slipstack does not produce it.
Is Slipstack Veri*Factu-certified?
No. Veri*Factu (RD 1007/2023) governs invoicing-software tamper-evidence and reporting; Slipstack is an invoice-generation API, not a certified Veri*Factu billing system.
Can I use Slipstack for the Spanish B2B mandate?
You can use it to generate and validate the EN 16931 UBL/CII structured invoice, which is among the formats the mandate is expected to accept; you still need a certified platform to submit, sign, and report status.
Related: France mandate · Italy mandate · EN 16931 explained · What is a PDP · Validate an invoice free.
Generate EN 16931 core invoices from one JSON call
Emit compliant UBL / CII XML or a Factur-X PDF, and validate the core rules for free first. For Spain’s mandates, bring a Spanish-certified platform for Facturae / FACe and Veri*Factu.