Mandatory B2B E-Invoicing in Spain: The Real Deadlines (2027–2028) and the Order to Prepare In

Mandatory B2B E-Invoicing in Spain: The Real Deadlines, and the Order You Should Prepare In

If you came here expecting a 2026 deadline, correct it now. Mandatory B2B e-invoicing in Spain starts on 1 October 2027 for businesses with turnover above €8 million, and on 1 October 2028 for everyone else — every remaining company, SME and self-employed professional. Those dates come from Royal Decree 238/2026, published in the BOE on 31 March 2026, and they are counted as 12 and 24 months from the entry into force of the Ministerial Order that governs the AEAT public solution, planned for 1 October 2026. There is a third date almost every guide skips: 1 October 2029, when reporting invoice *status* becomes mandatory for businesses and self-employed under €8M, who get twelve extra months for that specific obligation.

Here is the part that changes what you should do on Monday, and that the top-ranking summaries leave out: there is a correct order, and it isn't the obvious one. Before any e-invoicing date, Verifactu hits — 1 January 2027 for corporate income tax payers and 1 July 2027 for the rest, after the extension in Royal Decree-Law 15/2025. So the real sequence for a Spanish SMB is: (1) Verifactu-compliant issuing software, (2) structured e-invoice issuing, (3) receiving and status reporting. Most companies plan only for step 2, buy an issuing tool, and then discover that the expensive problem was step 3.

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The dates, in one place

1 October 2026 — Ministerial Order expected to enter into force. All the countdowns start here. (The draft went to public consultation until 8 May 2026 and, at the time of writing, is still pending final publication in the BOE.)
1 January 2027 — Verifactu mandatory for corporate income tax payers (SL, SA and similar).
1 July 2027 — Verifactu mandatory for the rest (self-employed and other taxpayers).
1 August 2027 — the AEAT public solution must be operational.
1 October 2027 — e-invoicing mandatory for businesses with turnover over €8M.
1 October 2028 — e-invoicing mandatory for all remaining businesses and professionals.
1 October 2029 — invoice-status reporting mandatory for those under €8M.

Why the order matters more than the dates

Verifactu and e-invoicing are two different obligations that people keep merging into one project. Verifactu is about *how your billing software records and chains what you issue*. Mandatory e-invoicing is about *the format and the route an invoice travels between two businesses*, plus what the recipient has to report back.

The practical consequence: if you replace your billing software in 2026 without asking the vendor about structured formats and the public solution, you will replace it again in 2027. Ask both questions in the same conversation — Verifactu records and UBL/Facturae output — and you buy once.

And if you're a gestoría or an accounting firm, the order is different again: your clients' Verifactu deadline (January and July 2027) lands before your own e-invoice issuing deadline. You'll be answering client questions about one regime while preparing for another. Our breakdown of what Verifactu really means for the way you handle invoices covers that first wave in detail.

The part nobody is preparing: receiving

Issuing is a software problem, and software vendors will solve it for you. Receiving is a *process* problem, and nobody sells you a process.

From the moment you're in scope, as a recipient you must report back, within four calendar days excluding Saturdays, Sundays and national holidays, at least: commercial acceptance or rejection of the invoice, with its date, and the date of full effective payment — defined as the day the supplier actually receives the funds. Partial acceptance, partial payment and assignment to third parties are optional statuses.

Read that again with your own operation in mind. It means someone has to *look at* every supplier invoice within four working days and decide whether it's accepted. Today, in most SMBs, supplier invoices sit in an inbox until somebody batches them at month end — or until the quarter closes and the accountant chases them.

Do the arithmetic with your own numbers

Take the invoices you receive per month and split them into two piles: the ones already reviewed within four working days of arrival, and the ones that aren't. A property manager receiving 300 supplier invoices a month who reviews them in a monthly batch has, by definition, 300 invoices a month that would miss the window. A firm that reviews weekly on Fridays misses only the ones that arrive Friday afternoon through Tuesday — roughly half.

Now multiply the second pile by the minutes it takes one person to open the invoice, identify the supplier, check the amounts against the delivery note or work order, and mark it accepted. If that's four minutes and you have 300 invoices, you're looking at 20 hours a month of work that currently has no owner and no deadline, and that from 2027–2029 will have both.

That is the real cost of the mandate for most SMBs. Not the e-invoice format — the review cadence behind it.

The mixed inbox: October 2027 to October 2028

For twelve months there will be two regimes running side by side. Your large suppliers are already obliged; you may not be. During the first twelve months of each wave, issuers must accompany the structured e-invoice with a PDF ensuring legibility, unless the recipient expressly agrees to receive the structured format alone.

So your 2027–2028 inbox will contain: structured XML from big suppliers, XML plus a courtesy PDF from most of them, plain PDFs from small suppliers not yet in scope, and photos of receipts from the ones who will never change. Any process that assumes a single input format will break in that window.

The pragmatic answer is to normalise everything to the same structured record on arrival, regardless of how it came in. That is exactly the reasoning behind sending invoices to Excel or your ERP through an API rather than making each source fit a different pipeline.

Formats: what's actually accepted

The regulation builds on the EN 16931 semantic model, and private platforms may exchange invoices in UBL (ISO/IEC 19845), CII (UN/CEFACT XML), EDIFACT (ISO 9735) or Facturae. A faithful copy of every invoice must also reach the AEAT public solution; the exact syntax required for that copy is one of the points the Ministerial Order settles, and it is precisely why you should not let a vendor sell you a format guarantee before the final text is in the BOE.

One thing is already unambiguous: a PDF is not an electronic invoice for these purposes. A PDF attached to an email will remain a legible copy, not the legal instrument.

A preparation order that actually works

Inventory your suppliers by size. The ones over €8M turnover are the ones that will start sending you structured invoices in October 2027. That's your real first deadline, and it's a *receiving* one.
Fix your issuing software once. Verifactu plus structured output, same purchase decision, before January 2027.
Set a review cadence now, before it's compulsory. Move from monthly batching to a rhythm that fits inside four working days. Doing this in 2026 is a process improvement; doing it in 2028 is a compliance emergency.
Decide who owns "accept or reject". The four-day clock needs a named person and a substitute for holidays, not a shared mailbox.
Normalise the data on arrival. Whatever the format, get supplier, tax ID, invoice number, date, base, VAT and total into the same structured record the moment it lands. If the data is already extracted, the accept/reject decision takes seconds instead of minutes.
Clean up your master data. Tax IDs and supplier names that don't match will be the first thing that fails automated matching. Our guide on preparing supplier invoices before handing them to your accountant is a decent template for what "clean" means.

Three mistakes with a real price tag

Treating this as an IT project with a 2027 start date. The behavioural change — reviewing invoices weekly instead of monthly — takes months to bed in and doesn't depend on any software. Start it now, at zero cost.

Assuming your ERP vendor covers status reporting. Most roadmaps announced so far cover issuing. Ask specifically, in writing, whether the product reports acceptance and payment dates to the public solution, and from when.

Letting VAT classification errors ride until the data is machine-readable. Once invoices are structured and cross-checked, the mismatches you currently absorb quietly become visible discrepancies. The most common mistakes when classifying VAT on supplier invoices are worth fixing before someone else's system flags them for you.

The one-line summary

The deadline everyone quotes (October 2027 / October 2028) is about the invoices you *send*. The deadline that will actually hurt is the four-working-day clock on the invoices you *receive* — and the only way to survive it is to stop letting supplier invoices pile up unread. That habit is free to change and pays for itself long before 2027.

Want to see what structured extraction looks like on one of your own invoices? Try it free — no signup.

Frequently asked questions

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