Second-ranked Siam Commercial Bank on Thursday reported a 4.6% decline in first-quarter net profit due to rise in costs and investments in digital banking.
Siam Commercial Bank's profit of 11.4 billion baht for the three months ended in March compared to 11.9 billion baht in the same period a year earlier. That missed the average 11.7-billion-baht estimate in a Reuters survey of three analysts.
The decline in profits was due to marketing expenses relating to getting more customers to use mobile and digital banking services, it said in a statement.
Last month, the country's largest banks said they would waive fees for digital transactions, a major source of non-interest income as customers turned to non-banking alternatives for payments and transfers.
SCB's operating expenses rose 20.6% from a year earlier.
The bank was focused on "speed and high security of our digital banking platform," chief executive Arthid Nanthawithaya said in a statement.
Mobile banking will be a source of future business opportunities, Mr Arthid said.
Earlier this year, Siam Commercial Bank said it would reduce headcount and branches and shift its focus to digital banking.