ING, a systemically important bank in the European Union that was rescued in 2008 with 10 billion euros, has managed to distance itself from the reputation problems that worry the banking sector in Spain. The Dutch bank entered the market in 1999 as an "outsider," and its first operations were carried out by telephone in a time when Internet penetration was not as significant as it is today.

Despite having only 1,419 employees, ING boasts a total of 3.9 million clients in Spain. While this figure still falls short of its larger competitors, such as CaixaBank, BBVA, Santander, and Bankia, the bank has a high ratio of clients per employee. For instance, ING has 2,748 clients per employee and 1,550 payroll accounts per employee, which is closer to online banking figures and far ahead of its larger Spanish competitors.

Despite the relatively small size of ING in Spain, it has been able to outperform CaixaBank and Bankia in terms of employee productivity, despite not having a Spanish banking license and benefiting from the central, technological, and regulatory support provided by its headquarters in Amsterdam. Therefore, it is essential to consider the “headquarters effect” when comparing ING's figures with those of its competitors. Nevertheless, ING's success in positioning itself in Spain with the productivity of new online banks such as N26 or Revolut highlights the potential for a shift in traditional banking practices.

When comparing ING with two of the biggest international banks in Spain, BBVA, and Santander, it is worth considering the “headquarters effect” as well. BBVA has a slightly larger workforce of approximately 30,000 employees and 10 million accounts in Spain, giving the bank a ratio of approximately 333 clients per employee. Meanwhile, Santander has approximately 30,000 employees and eight million accounts in Spain, giving the bank a ratio of 266 clients per employee. Nonetheless, both banks receive a significant portion of their income from their operations in America (Brazil for Santander and Mexico for BBVA), and these figures may not reflect a fully accurate picture of employee productivity in their Spanish operations.