Mexico banks warn of unauthorized charges

Banamex, BBVA Mexico, Santander, Banco Azteca and Banorte issued a joint warning urging customers to monitor their accounts more closely after reports of unauthorized charges, identity impersonation attempts and unauthorized access detected in August 2026.

What are the banks warning about?

Banamex, BBVA Mexico, Santander, Banco Azteca and Banorte asked customers to review account activity more often and respond quickly to any transaction they do not recognize. The warning, reported by Ámbito, comes as complaints over unauthorized transactions continue to rise before Condusef.

The clearest signal is in the complaints. Condusef said unauthorized purchases were the leading source of complaints in Mexico in the first half of 2026, with 19,197 cases, 29.2% more than a year earlier. In that same period, the different types of unrecognized operations, charges and movements totaled 42,897 complaints.

The second most common complaint was an unrecognized electronic transfer, with 8,306 cases, 17.9% more than in the same period of 2025.

What is Condusef seeing?

Condusef again recommended that, if a customer spots an unauthorized charge, they should report the transaction to the bank immediately and ask for the card to be blocked or canceled to prevent further activity. El Heraldo de Saltillo said that between January and May 2026, unauthorized purchases remained among the top reasons for complaints from financial services users.

Infobae detailed warning signs that Condusef considers indicators of banking fraud. They include messages, calls or emails that promise prizes or gifts and then ask for personal or financial information, as well as phrases like "we detected an unauthorized charge" or "we need to verify your identity."

The official recommendation, according to that reporting, is not to share passwords, PINs or SMS codes, and to verify any supposed prize or contact directly with the institution involved.