The debate over the validity of paper books and invoices in PDF or print formats is a recurring concern for professionals and small business owners who have always managed their accounting the traditional way. With Royal Decree 10072023 and the future full implementation of electronic invoicing in Spain, the question has new, clear answers. The technological transition is not immediate, but it is irreversible.​

Paper books or PDF files will still be considered valid during the transitional phase, provided the IT system that generates them meets basic traceability, integrity, and record retention requirements. If your paper invoices come from a system that does not comply with the law (for example, standard Excel, Word, or a regular printer), you will start encountering validity issues. The Tax Office will only accept structured electronic receipts with digital fingerprints, proving no data manipulation has occurred and allowing electronic tracking of every transaction.​

When do paper books and invoices lose validity?
The requirement to migrate to digital records starts in 2026 for large companies and in 2027 for small businesses and freelancers, unless special extensions apply. Until then, you may continue submitting books or invoices in PDF as long as you can access the original digital files and metadata generated by certified software on demand. For inspections, simple Excel lists or traditional physical binders will no longer be sufficient.​

The smart move is to migrate management to electronic formats as soon as possible, digitizing both issued and received invoices. Also, it’s advisable to scan and archive older documents and, from 2026, demand valid digital receipts from suppliers, since only these can be deducted for tax purposes.​

Practical Advice for Freelancers and SMEs:

1. Check if your software is adapted to the new rules and can export records in structured electronic format XML, FacturaE, UBL.​

2. Ask your advisor or provider to audit your system and check whether your books and invoices are valid for deduction and inspection beyond 2026.​

3. Don’t rely solely on paper—keep it as a backup, not as your only justification.​

4. Periodically review your expense documentation and make sure your entire accounting cycle is digitized and traceable.​

Conclusion:
Although today you can still submit books and invoices in paper or PDF, switching to digital management is mandatory in the coming years. Getting ahead saves time, avoids problems, and ensures all your documents will be valid before the Tax Office according to future law and control standards.