Why are Excel and Word
Banned for Issuing Invoices?
With the approval of the VeriFactu technical regulation, the traditional editable Excel and Word templates are no longer legal in Spain. Here are the legal reasons why.
Why is Excel/Word illegal?
- Direct manipulation: Figures, descriptions and dates can be changed or deleted at any time without leaving a trace.
- No SHA-256 chaining: There is no encrypted sequential record guaranteeing that invoice 2 was created after invoice 1 in a way that cannot be altered.
- No official certification: Neither Microsoft Excel nor Google Sheets holds (nor will hold) a responsible declaration of tax compliance before the AEAT (the Spanish Tax Agency).
The 5 Mandatory Technical Requirements
- Unalterability: Once an invoice has been saved, its data cannot be modified under any circumstances.
- Traceability: Any correction must generate a new document linked to the previous one.
- Retention: The software must guarantee secure storage for a minimum of 4 years.
- Readability: The data must be available in a standard structured format for quick export.
Comparison Table: Templates vs Certified Software
| Feature | Excel / Word (Template) | Fakturia (VeriFactu) |
|---|---|---|
| Legal in 2026/2027? | No (banned by the Anti-Fraud Law) | Yes (100% certified) |
| Mandatory AEAT QR code | Not available (impossible to generate automatically) | Generated automatically in the PDF |
| SHA-256 chaining | No (files are independent and can be altered) | Yes (an unbreakable mathematical chain) |
| Risk of a €50,000 fine | Very high (for holding uncertified software) | Zero |
The ban on dual-use software
Law 11/2021 on measures to prevent and combat tax fraud targets the possession and use of software that makes it possible to hide sales or keep a second set of books (dual-use software). Because spreadsheets such as Excel allow any cell to be changed without leaving an unalterable audit log, the Tax Agency legally treats them as invalid tools for documenting professional income.
Frequently Asked Questions (FAQ)
Can I fill in the Excel file and save it as a non-editable PDF?
No. Even though the final PDF sent to your client cannot be edited, the tool used to create it (Excel) can be, and it has no signatures or chained SHA-256 hashes in its underlying database. The offence is committed the moment the invoice is generated in a system that is not compliant.
Are there fines for a freelancer who uses Excel?
Yes. Holding an uncertified system as the end user (freelancer or company) carries fixed fines of €50,000 per financial year, on top of any penalties for irregularities in your tax returns.
Leave Excel behind. Move to the VeriFactu standard.
Fakturia.es makes issuing invoices as simple as filling in a spreadsheet, but with the complete peace of mind of being 100% compliant with the Tax Agency's servers.