With so many tax acronyms —SII, VeriFactu, TicketBAI— it's easy to get confused and not know what applies to you. The most common confusion is between SII and VeriFactu: they sound similar, but they are different things and don't apply to the same type of company. This guide clarifies what each one is, how they differ, who they affect, and how Odoo covers them, so you know where you stand. As always in tax matters, it's advisable to confirm the specifics of your case with the AEAT or your tax advisor.
En 30 segundos. SII vs VeriFactu: Understand each, key differences, who it applies to, and compatibility. See how Odoo covers them. An official Odoo partner guide.
What is SII (in one sentence)
SII, Immediate Supply of Information (Suministro Inmediato de Información), is the system by which certain companies submit their VAT record books through the Tax Agency's online portal, sending invoice data within a short period of days. Its key feature is the immediacy of VAT information. You can find it developed in our guide on SII with Odoo.
What is VeriFactu (in one sentence)
VeriFactu is the system that guarantees that the invoicing software produces invoices that cannot be altered or deleted without leaving a trace: it signs them, chains them, and allows for their verification. Its key feature is the integrity of the invoicing record. You can find it developed in VeriFactu and Odoo.
How they differ
Although both aim for more transparent invoicing, they address different aspects:
| SII | VeriFactu | |
|---|---|---|
| What it's about | VAT ledgers in near real-time | Tamper-proof invoicing record |
| What it requires | Submit VAT records within days | That the software signs and chains invoices |
| Who it applies to | Large companies, monthly VAT declarants | Generally, those not covered by SII (2026) |
| Focus | VAT information to the Tax Office | Integrity of the invoicing software |
Indicative comparison; the specific application depends on your situation and should be confirmed with the AEAT or your tax advisor.
Are they compatible or mutually exclusive?
This is the most frequently asked question. The system's logic is that they do not overlap: whoever is covered by SII already reports their invoices to the Tax Office almost in real time, so, generally, they fall outside the scope of VeriFactu. And VeriFactu is aimed at those not covered by SII. That is, for most companies, the question is not 'SII and VeriFactu,' but 'SII or VeriFactu,' depending on their profile. That said, the nuances are set by the regulations and your specific case, so this point — which one applies to you — is precisely what you should confirm with your tax advisor.
And TicketBAI, where does it fit in?
To complete the picture: TicketBAI is the regional equivalent of VeriFactu in the Basque Country and Navarre. If you operate in common territory, your reference is VeriFactu (or SII, depending on your profile); if you operate in regional territory, TicketBAI. You can find it in the guide on TicketBAI and Odoo.
How Odoo covers it
The good news is that you don't have to choose one software for SII and another for VeriFactu: Odoo covers both depending on your location and the configuration activated for your case. If you're covered by SII, Odoo sends VAT records within the deadline; if VeriFactu applies to you, it issues invoices according to that system. The invoicing that powers all of this is in Odoo Invoicing, and the project framework in Odoo implementation.
What to do to avoid mistakes
In practice, the sensible approach is this: confirm with your tax advisor which one applies to you —usually one or the other depending on your profile—, make sure your software is ready for that system, and get it properly configured from the outset instead of rushing when the deadline approaches. With a partner familiar with Spanish localisation, this can be resolved once and for all; it's advisable to choose wisely.
Why they are so often confused
The confusion between SII and VeriFactu is logical: both have to do with invoicing, both involve the Tax Office, and both seek greater transparency. But they tackle the problem from different angles. SII looks at VAT ledgers and wants the information as soon as possible; VeriFactu looks at the invoicing software and wants invoices to be tamper-proof. It's like confusing warehouse control with till control: both monitor, but different things. The key to avoiding confusion is to grasp the underlying idea: SII = real-time VAT information; VeriFactu = invoices that cannot be tampered with. And, above all, remember that for most companies it's not 'both,' but 'one or the other' depending on their profile.
What to do according to your profile
In practice, the useful question is 'what applies to me?', and the answer usually depends on your size and how you declare VAT. If you are a large company or declare VAT monthly, you are likely to be covered by SII. If you are an SME or a self-employed individual under the general quarterly VAT regime, your usual reference is VeriFactu from 2026. And if you operate in the Basque Country or Navarre, TicketBAI. But these are general rules: the nuances are set by the regulations and your specific case, so the sensible step is to confirm it with your tax advisor and, with that answer, ensure your software is ready for the system that applies to you. Odoo covers all three depending on the configuration, so the important decision is not the software, but knowing what your obligation is.
Frequently Asked Questions
What is the difference between SII and VeriFactu?
SII concerns submitting VAT ledgers to the Tax Office almost in real time; VeriFactu, about ensuring invoicing software produces tamper-proof invoices. They are different obligations for different profiles.
Do I have to comply with both simultaneously?
Generally, no: whoever is covered by SII falls outside the scope of VeriFactu, because they already report in real time. For most, it's one or the other, depending on their profile. Confirm it with your tax advisor.
Who does SII apply to?
Mainly to large companies and those who declare VAT monthly (REDEME, VAT groups). For the rest, it is voluntary.
Who does VeriFactu apply to?
Generally, from 2026, to those not covered by SII. It is the system designed for the majority of companies and self-employed individuals in common territory.
And TicketBAI?
It is the regional equivalent of VeriFactu in the Basque Country and Navarre. If you operate there, your reference is TicketBAI instead of VeriFactu.
Does Odoo work for SII and VeriFactu?
Yes. Odoo covers both depending on your location and the configuration activated for your case, without the need for two different software programs.
How do I know which one applies to me?
It depends on your profile (whether you declare VAT monthly, your size, your territory). It's precisely the kind of thing you should confirm with the AEAT or your tax advisor.
What happens if I don't comply with the one that applies to me?
There may be penalties and, in practice, problems with normal invoicing. That's why it's advisable to have the software prepared and well-configured in advance.
Do SII and VeriFactu apply throughout Spain?
They apply to common territory; in the Basque Country and Navarre, the reference is TicketBAI, their regional equivalent. If you operate in several territories, you comply with the one that corresponds to each.
Do I need to change software to comply?
Not necessarily, but your software must be ready for the system that applies to you. Odoo covers SII, VeriFactu, and TicketBAI depending on the configuration, so if you already use it, you're covered.
Are you unsure whether SII or VeriFactu applies to you?
At Nextdoo, an official Odoo partner, we ensure your invoicing complies with the system applicable to your case. Start by VeriFactu and Odoo or request a diagnosis for your company.
Sources: Tax Agency's online portal and Odoo documentation. Indicative information, not tax advice; confirm which one applies to you with the AEAT or your tax advisor.
Sources
Official sources consulted: official Odoo documentation y Tax Agency's online portal (VeriFactu). Cost and timeline figures are indicative and non-binding, subject to variations depending on the project.