The tax administration warns that citizens are receiving fraudulent phone calls on behalf of the tax authorities, in which they are asked to correct a supposed divergence in the IRS declaration.
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22/08/2026
by
Lusa
As calls are part of a ‘vishing’ campaign, where “the recipients of these calls are asked to press a particular key to allegedly “correct a divergence in the income statement,” explains the Tax and Customs Authority (AT) in a message published this week on the Finance Portal.
Phone contacts take place at a time when the deadline for the delivery of income declarations for 2025 has already expired and at a time when the tax authorities have already had to settle the files (to complete the process of calculating the tax and notifying taxpayers of the final result, whether it results in a refund, money to be delivered to the State, or nothing to receive or pay).
The so-called “must be ignored”, recommends the tax.
In the same notice, AT notes that fraudulent ‘e-mails’ are circulating where attackers ask recipients to click on certain links and text messages by mobile phone (SMS) in order to induce people to validate personal data.
Vishing is a kind of attack in which social engineering techniques are used, using voice messages or phone calls, with the aim of capturing sensitive information from a victim, explains the National Cybersecurity Center (CNCS). The term results from the combination of English words ‘voice’ and ‘phishing’.
In this case, by simulating an institution to gain credibility, the attackers fraudulently invoke the name of the Tax and Customs Authority.
According to the report the “Cibersecurity in Portugal”, published by CNCS in April this year, “with the sustained increase in digital exposure of individuals and families to the internet and certain digital services increases the risk of cyberattacks”, with cases of social engineering and fraud, especially in the case of social engineering, to “the increase of vishing and CEO Fraud”.
In 2024, “the most frequently observed subtypes of social engineering were ‘vishing’ (18.31% of the total), CEO Fraud (17.89%), following the false recruitment techniques (11.6% of the total) and scams ‘Hello, Father... Hello, Mother’ (8.7%)’, says the CNCS in another September 2025 report of ‘Riscos & Conflicts’.