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 improper access detected in August 2026.

The banks' warning

As reported by Ámbito, the alert asks users to review their transactions more frequently and react quickly to any movement they do not recognize. The message comes as complaints over unauthorized transactions continue to climb at Condusef.

The clearest signal is in the complaints data. Condusef said unrecognized purchases were the top cause of complaints in Mexico in the first half of 2026, with 19,197 cases, up 29.2% from a year earlier. In that same period, different forms of unrecognized operations, charges and account movements totaled 42,897 complaints.

The second leading complaint category was unrecognized electronic transfers, with 8,306 cases, 17.9% more than in the same period of 2025.

What Condusef is seeing

El Heraldo de Saltillo reported that Condusef again recommended that, if a charge is not recognized, the user should immediately report the transaction to the bank and request that the card be blocked or canceled to prevent further activity. The same publication said that between January and May 2026, unrecognized purchases continued to rank among the main reasons financial users filed complaints.

Infobae, meanwhile, detailed warning signs that Condusef associates with banking fraud. These include messages, calls or emails that promise prizes or gifts and then ask for personal or financial information, as well as phrases such as "we detected an unrecognized charge" or "we need to verify your identity."

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