Kostaman Thayib began his career in the banking industry after joining Bank Central Asia in 1992. His career soared when he served as Senior Vice President and Group Head of Liabilities and Electronic Banking at PT. Bank Mandiri (Persero) in 2002. Kostaman was later appointed as the President Commissioner of PT. AXA Mandiri Financial Services Indonesia.

Currently, this 1982 graduate of the Faculty of Industrial Technology Universitas Trisakti serves as the President Director of Bank Mega.