The digitalization of tax control in Spain has driven the introduction of new systems aimed at improving the traceability of economic transactions and strengthening the fight against fraud. Among them, the Immediate Supply of Information (SII) and the VeriFactu system stand out, both integrated within the framework of electronic invoicing systems.
Although both aim to increase transparency in invoicing and tax compliance, their operation is different. While the SII focuses on the near real-time reporting of VAT records to the Spanish Tax Agency, VeriFactu acts directly on the software used to issue invoices.
What is SII?
The SII has been in operation since 2017 and requires certain companies to electronically send their VAT ledger records to the Spanish Tax Agency shortly after issuing or receiving an invoice.
This system mainly affects:
- Large companies with annual turnover exceeding €6,010,121.04
- Companies registered in the Monthly VAT Refund Register (REDEME)
- VAT groups.
The records must be submitted within a general deadline of four calendar days, which requires direct integration between accounting systems and VAT management.
What is VeriFactu?
The VeriFactu system is part of the regulation on Electronic Invoicing Systems established by Royal Decree 1007/2023. Its objective is to ensure that invoicing software generates secure, immutable, and verifiable records.
The regulation provides for two modes:
- VeriFactu system, with automatic transmission of invoicing records to the Spanish Tax Agency
- Non-VeriFactu system, in which the software generates a signed file that must be retained for possible audits.
Unlike the SII, VeriFactu focuses on how invoices are generated, ensuring data integrity from the source.
Differences between SII and VeriFactu
| Aspect | SII | VeriFactu |
| Implementation | Since 2017 | Gradual implementation until 2027 |
| What it controls | VAT ledger records | Invoicing records |
| Operation | Submission of records to the Spanish Tax Agency | Invoicing software with secure records |
| Who it affects | Large companies, REDEME and VAT groups | Companies and self-employed professionals |
Companies already required to comply with the SII will not be required to apply VeriFactu, as the level of tax control involved in the SII is considered sufficient.
Implementation timeline
The implementation timeline for VeriFactu has been postponed by Royal Decree-Law 15/2025, establishing the following dates:
- January 1, 2027 for corporations
- July 1, 2027 for other businesses and professionals.
In addition, the regulations provide for fines of up to €50,000 per financial year for software manufacturers or vendors who fail to comply with legal requirements or who allow manipulation of invoicing records.