When the AEAT (Spanish Tax Agency) drives two fiscal control initiatives with similar names and close deadlines, confusion is guaranteed. SII (Suministro Inmediato de Información — Immediate Supply of Information) and Verifactu (invoicing records verification system) are two separate obligations, affecting different groups of taxpayers, with different technical impacts and different deadlines. Confusing them can lead you to believe you are already covered when you still have work ahead, or conversely, to invest in adaptations that do not apply to you. This article clarifies exactly what each one is, how they differ, and what you need to review in your management system.
What is SII and who does it affect?
The Suministro Inmediato de Información (SII) is a system for keeping VAT record books through the AEAT Electronic Headquarters, introduced by Royal Decree 596/2016. Instead of submitting forms 340 and 347 periodically, obligated companies send records of issued and received invoices within a maximum of four business days after the date of issue or receipt.
SII has been mandatory since 1 July 2017 for the following groups:
- Large companies (volume of transactions exceeding 6,010,121.04 euros in the previous year).
- VAT groups registered in the Monthly Refund Register (REDEME).
- Taxable persons subject to the Special Group of Entities Regime (REGE).
Standard SMEs, self-employed individuals, and companies with a transaction volume below the threshold are not obligated to use SII, although they may voluntarily opt in. As of June 2026, more than 60,000 taxpayers operate under SII in Spain, according to AEAT data.
What is Verifactu and when does it come into force?
Verifactu is the invoicing records verification regime established by Royal Decree 1007/2023, of 5 December, which implements the Anti-Fraud Law 11/2021. Its objective is to guarantee the integrity and immutability of issued invoices through a system of chained records with a digital fingerprint (hash) in the invoicing software, with the possibility — and in many cases obligation — of sending those records to the AEAT in real time.
Verifactu applies to all entrepreneurs and professionals who issue invoices in Spain and use invoicing software to do so, regardless of their size or transaction volume. The main exceptions are taxpayers already subject to SII (who have their own traceability requirements) and certain special regimes.
The official deadlines, according to Royal Decree 1007/2023 as currently in force as of June 2026 — amended by Royal Decree 254/2025 and Royal Decree-law 15/2025 of 2 December — are:
- Large companies and groups (Corporate Income Tax taxpayers): adaptation before 1 January 2027.
- Remaining companies and self-employed: before 1 July 2027.
If your software provider has not yet communicated the Verifactu update to you, this is a red flag you need to address immediately.
Comparison table: SII vs Verifactu at a glance
| Aspect | SII | Verifactu |
|---|---|---|
| Legal basis | Royal Decree 596/2016 | Royal Decree 1007/2023 / Law 11/2021 |
| Who is affected? | Large companies, REDEME, REGE | All those who issue invoices using software (except SII and exceptions) |
| Volume threshold | More than 6 M€ in transactions | No threshold; affects SMEs and self-employed |
| What is sent to the AEAT? | Records of issued and received invoices | Invoicing records with chained hash (submission voluntary or mandatory depending on regime) |
| Submission deadline | 4 business days after issue | Immediate in «Verifactu» mode (at the moment of issuance) |
| Impact on software | Communication API with the AEAT (WSDL/SOAP) | Internal record chaining engine + QR code on invoice + possible submission to AEAT |
| Does it replace 347/340? | Yes, for obligated parties | No; it is an integrity control, not a periodic declaration |
| Compatible with each other? | Yes: those obligated to SII are exempt from Verifactu submission, but their software must also comply with the integrity requirements of RD 1007/2023 | |
| Start date | 1 July 2017 | 1 January 2027 (large companies) / 1 July 2027 (others) |
Can they coexist in the same company?
Yes, but with nuances. A company already in SII does not need to send its Verifactu records to the AEAT; however, its invoicing software must still comply with the technical requirements of Royal Decree 1007/2023: record chaining with hash, storage of invoicing records, and in many cases the printing of the verification QR code on the invoice. Being in SII is not a blank cheque to ignore Verifactu; it simply exempts you from real-time submission.
For SMEs not in SII, Verifactu is the only active obligation today. And the adaptation is not trivial: it requires the software to be certified by the provider, that historical data in the ERP is managed correctly, and that the invoice issuance process generates the control record automatically and in a chained manner.
What all this means for your ERP or invoicing software
If you use a market ERP such as Odoo, Sage 200, Microsoft Dynamics 365 Business Central, Holded, or any other invoicing software, the concrete impact you need to verify is the following:
For companies under SII
Your ERP should already have the SII module operational for several years. The question now is whether the updated version of that module also complies with the record integrity requirements of RD 1007/2023. Check with your provider whether they have published a Verifactu compliance update even if you are under SII. The answer should be affirmative.
For SMEs and self-employed (not SII)
The minimum checklist you need to confirm with your software provider:
- Does the software generate the invoicing record with the mandatory fields from RD 1007/2023 (issuer VAT number, invoice number, type, base, tax amount, date, previous hash)?
- Does it implement hash chaining SHA-256 between consecutive records?
- Does it include the QR code for verification in the invoice PDF?
- Is the software listed in the certified software list that the AEAT publishes on its electronic headquarters?
- Have the submission parameters been configured (voluntary or in Verifactu mode with immediate submission to the AEAT)?
If any of these answers is «no» or «I do not know», the company faces a real risk of non-compliance. The penalties established in Article 201 bis of the General Tax Law (introduced by Law 11/2021) for the use of non-compliant software are: 1,000 euros per system marketed without the required certification for producers and distributors; and up to 50,000 euros per fiscal year for users of non-compliant software, rising to 150,000 euros when the system incorporates dual-use functionality to conceal transactions.
Relationship between Verifactu and B2B electronic invoicing (Crea y Crece Act)
There is a third acronym that gets mixed into the conversation: the mandatory B2B electronic invoice required by Law 18/2022 (Crea y Crece). This is a separate obligation from Verifactu: it requires that invoices between companies be issued in a structured format (FacturaE or the new format to be defined by the implementing regulation) and exchanged through interoperable platforms.
As of June 2026, the implementing regulation for B2B electronic invoicing has not yet been approved in its final version, so the definitive entry-into-force deadlines are still pending official confirmation. However, the technical requirements of Verifactu are compatible with and in some cases complementary to B2B electronic invoicing: both systems require the software to generate invoices with structured and intact data.
If your ERP is being adapted for Verifactu, use that project to also review the state of readiness for B2B electronic invoicing. They are two separate projects, but they share technical infrastructure.
At Summum Sistemas we support SMEs and mid-sized companies in adapting their ERPs and invoicing software to both Verifactu and B2B electronic invoicing, with a prior technical gap analysis and a concrete implementation plan.
Common mistakes when mixing up SII and Verifactu
In real adaptation projects, Summum Sistemas repeatedly detects the following errors:
- Believing that being in SII exempts you from all Verifactu requirements. That is not the case: the software must meet the integrity requirements even if there is no submission to the AEAT.
- Trusting that the software provider handles everything without verifying it. The legally responsible party for compliance is the taxpayer, not the provider. Demand documentation of the certification.
- Applying only the update to the invoicing module without reviewing the ticket, delivery note, or credit note modules, which in some ERPs also generate invoicing records subject to Verifactu.
- Not keeping invoicing records for the legal retention period (minimum 4 years, in line with article 70 of the VAT Act). The Verifactu record is a tax document, not just a technical log.
- Launching the Verifactu system without having correctly configured the invoice series, which creates a mismatch in hash chaining that invalidates the sequence from the very first record.
How does Verifactu affect a multi-company or multi-site ERP?
In environments with several companies or branches issuing invoices from the same ERP, each issuer VAT number has its own Verifactu record chain. You cannot mix the chain of one company with that of another. If the ERP manages several legal entities under the same system, the configuration must ensure that the counters and hash chains are independent per VAT number. This point usually requires specific technical intervention in the module configuration.
Likewise, test or staging environments that also issue invoices must be clear about whether they use the AEAT test environment (which exists for Verifactu submission) or whether the invoices generated in those environments are correctly marked as «non-productive» to avoid contaminating the real chain.
Frequently asked questions
My company is in SII: do I need to do anything about Verifactu?
Yes. Even though you do not have to submit Verifactu records to the AEAT, your invoicing software must still comply with the technical requirements of Royal Decree 1007/2023: record chaining with hash, mandatory fields, and record storage. Check with your ERP provider whether the Verifactu compliance update is already available and installed in your system.
What is the practical difference between «Verifactu software» and «non-Verifactu software»?
Royal Decree 1007/2023 distinguishes two modes for the software: the «Verifactu» mode, in which the software automatically sends each invoicing record to the AEAT at the moment of issuance, and the «non-Verifactu» mode (also called computerised systems with records), in which the software generates and stores the records with hash chaining but does not submit them in real time, although the AEAT can request them at any time. Both modes are legally valid, but the Verifactu mode with immediate submission offers greater legal certainty because each invoice is «sealed» on the AEAT servers.
What happens if the July 2027 deadline passes and my software is not adapted?
Using invoicing software that does not comply with the requirements of RD 1007/2023 constitutes a tax infringement under Law 11/2021. For the software user, sanctions can range from 1,000 euros for a minor infringement to significantly higher amounts depending on the severity and type of non-compliance. Moreover, failure to comply can compromise the tax validity of issued invoices, creating risk for your business clients in terms of VAT deductions. The risk of delay is not just a one-off fine; it is a reputational risk with your business customers.
Can I keep using Excel or a spreadsheet to invoice?
Generic spreadsheets (Excel, Google Sheets, LibreOffice Calc) are not invoicing software within the meaning of RD 1007/2023 and cannot meet the requirements for hash chaining and QR code generation. If you currently issue invoices from a spreadsheet, you are required to migrate to certified invoicing software before 1 July 2027. There are free or low-cost options that are already certified, but if your transaction volume justifies an ERP, this is the moment to take that step.
If you need guidance on which technical solution best fits your situation — whether a full ERP, an invoicing module, or an integration with your current system — the team at Summum Sistemas can help you map the shortest path to compliance, with more than 15 years of experience in management software implementations for SMEs in Castilla y León and the Canary Islands.