In 2002, Banthoon became president and CEO of TFB. In 2003, he changed the logo and name of the bank from Thai Farmers Bank (TFB) to the current name, Kasikornbank (KBank), improvising Chinese characters style into the logo, "K". In 2010, after Dr. Prasarn Trairatvorakul, then the president of KBank, left to become the Governor of the Bank of Thailand, Banthoon assumed the role of both president and CEO of KBank. He also instituted a senior executive position called "domain coordinator" and nominated four executive vice presidents to assume the positions of business domain, risk domain, infrastructure domain, and resource domain. Two of these executives later became the presidents of KBank and the other two became board directors.
2002 President and Chief Executive Officer, Thai Farmers Bank