If you use Factusol to issue invoices, you have probably heard about Verifactu in recent months. The term sounds technical, but the question that matters is simple: do I need to do anything with my software before the end of 2027? The answer is yes, and it is worth understanding it properly so you do not fall behind.
In this article we explain what Verifactu is, why it affects Factusol users, what the exact deadlines are and what steps to take to comply without disrupting your daily invoicing. If you need specialist support, our Factusol implementation and support service has been helping SMEs and accounting firms through this kind of transition since 2007.
What is Verifactu and why does it exist?
Verifactu is the verified invoicing system regulated by Royal Decree 1007/2023 and developed within the framework of Anti-Fraud Law 11/2021. Its aim is to ensure that invoicing records cannot be tampered with: each invoice issued is cryptographically chained to the previous ones (registration record, hash, integrity fingerprint) and can be sent in real time to the AEAT (Spanish Tax Agency) or consulted afterwards.
The mechanism is NOT an accreditation or certification by the AEAT. Software that complies with Verifactu does so through a manufacturer's declaration of conformity under RD 1007/2023. There is no official seal of "AEAT-certified software"; any supplier claiming otherwise is using incorrect language.
Verifactu and the SII (Immediate Supply of Information) are mutually exclusive regimes: businesses already enrolled in the SII (mandatory for those exceeding 6 million euros in annual turnover) do not have to adopt Verifactu.
When does it come into force for your business?
| Type of taxpayer | Verifactu deadline | SII obligation (if applicable) |
|---|---|---|
| Legal entities (S.L., S.A., cooperatives…) | 1 January 2027 | SII if >6 M€/year (already active, excludes Verifactu) |
| Self-employed individuals (sole traders in economic activity) | 1 July 2027 | SII if >6 M€/year (excludes Verifactu) |
| Businesses already under SII | Verifactu does not apply | SII already active |
Even though the deadlines may seem distant, the adaptation requires configuring the software, migrating historical data if you change version and validating that invoice numbering remains sequential. Leaving it to the last quarter poses a real risk of operational disruption.
Factusol and Verifactu: what has changed in the software?
Software del Sol (DELSOL), the Jaen-based company acquired by TeamSystem in February 2021 and belonging to the largest Italian software group for SME management, has adapted Factusol to the Verifactu regulation. The adaptation is available in the cloud version and in the updated desktop version.
The main changes in Factusol are:
- Generation of the registration record: each invoice issued automatically creates a record with a hash fingerprint that chains the current invoice to the previous one.
- QR code on the document: printed invoices include a QR code that allows any recipient to verify the authenticity of the document with the AEAT.
- Submission to the AEAT (Verifactu mode): in active mode, Factusol can transmit records in real time to the Tax Agency's servers without manual intervention.
- SINREGISTRO mode: for those who prefer to keep the local record without automatic submission, the regulation also allows this, provided the file is available for inspection.
- Integrity and unalterability: the system prevents invoices already registered from being modified or deleted without leaving an auditable trail.
What does not change is the usual workflow: creating quotes, orders, delivery notes and invoices in Factusol remains the same. The Verifactu layer operates in the background.
What happens if you stay on an old version of Factusol?
This is the critical point for many businesses. Until a few years ago, Factusol was free and many self-employed individuals and small businesses installed it without contracting any support or updates. With the acquisition by TeamSystem, the model changed to a subscription: the updated versions with Verifactu require an active plan.
If your Factusol installation does not receive updates, from the dates indicated above you will be using software that does not comply with tax regulations. The consequences can range from penalties by the AEAT to the invalidity of invoices issued during an audit.
Factusol cloud plans have a list price starting at approximately 19.50 EUR/month for the basic tier, with higher plans up to around 82 EUR/month depending on features and users (manufacturer prices, subject to change; check current rates at sdelsol.com).
Factusol in the TeamSystem ecosystem: more than invoicing software
Factusol handles invoicing, stock control and purchases/sales, but it is not accounting software. To close the accounting cycle, the natural solution within the TeamSystem/DELSOL ecosystem is to integrate it with Contasol (professional accounting with SII) or with the DELSOL 360 suite, which brings together Factusol, Contasol and Nominasol on an integrated cloud platform.
For tax and payroll advisory firms, the broadest solution within the group is Aplifisa (Salamanca, 1983), which includes its own invoicing module — FactuGes — already adapted to Verifactu, as well as accounting with SII, the Tax Suite (Income Tax, Corporate Tax, VAT), the Labour Suite and practice management.
How to prepare for the Verifactu migration in Factusol: practical steps
The transition is not simply a matter of installing an update. These are the steps we recommend at Summum Sistemas, Official Partner of TeamSystem:
- Audit your current version. Check which version of Factusol you have installed and whether it is within active support. If you have not updated for years, the jump may involve adjustments to your invoice series configuration.
- Review the Verifactu mode you need. Real-time submission to the AEAT or local record mode? For most SMEs, automatic submission simplifies traceability; for accounting firms managing multiple clients, it may be worth reviewing the options for each business.
- Validate numbering and series. The regulation requires invoice numbering to be sequential with no gaps within each series. If you have had interruptions or deleted invoices in the past, the historical records need to be cleaned up before activating Verifactu.
- Update or take out a subscription plan. If you are on an unsupported version, now is the time to regularise the licence and verify that the update includes the validated Verifactu module.
- Test in the AEAT sandbox. Before activating real submission, the AEAT provides a test environment (sandbox) to validate that records are generated correctly.
- Train your team. Staff who issue invoices must know that they can no longer modify them once registered without generating a rectification document.
If you need someone external to guide you through this process, Summum Sistemas offers Factusol implementation, migration and support with a presence in Castilla y León (Valladolid, Burgos, Palencia, Aranda de Duero) and in Las Palmas.
Comparison: Factusol versions and modes in 2026
| Mode | Verifactu included | Cloud / Desktop | Indicative price |
|---|---|---|---|
| Factusol free version (discontinued) | No | Desktop | Free (no support or updates) |
| Factusol Cloud Basic | Yes | Cloud | From ~19.50 EUR/month (indicative) |
| Factusol Cloud Superior | Yes | Cloud | Up to ~82 EUR/month (indicative) |
| DELSOL 360 (integrated suite) | Yes | Cloud | See sdelsol.com |
Prices from the manufacturer Software del Sol (DELSOL/TeamSystem), indicative and subject to change. Check the current rates at sdelsol.com before making a decision.
Verifactu and B2B electronic invoicing: are they the same thing?
No. It is a common mistake to confuse them. Verifactu regulates the integrity and traceability of computer invoicing systems (RD 1007/2023). B2B electronic invoicing — mandatory between businesses — is regulated by Law 18/2022 (the Create and Grow Act) and its implementing regulation is still pending final approval. These are two separate obligations with different timetables.
Factusol covers Verifactu. For B2B electronic invoicing in structured formats (Facturae, UBL…), it is worth keeping an eye on the implementing regulation of the Create and Grow Act, expected to apply from 2026–2027 depending on company size.
Frequently asked questions
Does Factusol comply with Verifactu without me doing anything?
Not automatically. The Verifactu functionality is available in updated versions of Factusol, but you must activate and configure it correctly: choose the submission mode (real time to the AEAT or local record), review your invoice series and make sure your licence is up to date. If you have not updated for some time, you may need to migrate to a current subscription plan. A Factusol consultant can carry out this review in a few hours.
Can I keep using Factusol without Verifactu until the deadline arrives?
Technically yes, until 1 January 2027 if you are a legal entity, or until 1 July 2027 if you are self-employed. However, we do not recommend waiting until the last moment: the migration may reveal issues with invoice numbering or system configuration that take time to resolve. The usual approach is to plan the adaptation at least three or four months in advance.
Can Factusol also handle accounting?
No. Factusol is invoicing, stock management and purchase/sales software, but it does not generate accounting entries or tax returns (VAT, income tax, corporate tax). For accounting, the natural complementary software within the TeamSystem/DELSOL ecosystem is Contasol. Both integrate and allow Factusol transactions to be exported directly to the accounts, closing the cycle without double data entry.
Is Verifactu the same as AEAT accreditation?
There is no such thing as AEAT "accreditation" of invoicing software. The legal mechanism is the manufacturer's declaration of conformity under Royal Decree 1007/2023: it is the manufacturer itself (in this case, Software del Sol / TeamSystem) that declares its product meets the technical requirements of the regulation. The AEAT does not certify or endorse specific brands or products. Be wary of any supplier claiming to hold an official Tax Agency seal.