What Is “Dual-Use Software” and Why Is the Spanish Tax Agency Cracking Down on It?

The Spanish Tax Agency (AEAT) has launched an intensive control campaign targeting the use of so-called dual-use software — a type of program that many businesses may unknowingly be using, but that poses significant legal and financial risks.

What is dual-use software?

This type of software includes standard functions (such as recording sales, issuing invoices, and tracking stock) as well as hidden features that allow records to be altered or deleted. The goal: to hide real income and pay less tax.

Common functionalities include:

• Deleting or altering already-issued invoices or tickets.

• Hiding cash transactions.

• Creating false invoices with lower amounts.

• Manipulating inventory records to justify undeclared goods.

These systems allow companies to maintain a parallel accounting system — commonly known as "shadow accounting."

Why is the Tax Agency acting now?

The AEAT has seen a growing use of these tools, particularly in cash-intensive sectors such as hospitality, retail, and services. In response, it is now conducting in-depth IT audits to uncover hidden manipulation features in business software.

Consequences of using dual-use software:

• Heavy fines, depending on the scale of the fraud.

• Criminal liability for serious cases of tax evasion.

• Reputational damage, which can impact relationships with clients and suppliers.

Could I be using it without knowing?

Yes. Some businesses purchase software solutions unaware that they contain illegal functionalities. To avoid this, it’s essential to:

• Ensure your software complies with current tax regulations.

• Keep systems up to date using trusted providers.

• Train staff in accurate financial practices.

• Periodically audit internal records and processes.

At Valero Tax Legal, we encourage business owners to take a proactive approach. A technical and legal audit can identify risks early and help you stay protected.