Kris Chantanotoke, an executive vice president, said that once Basel III come into effect, subordinted debentures would carry a higher cost.
The issue offers 4.65 per cent in annual coupon rate. It would be available for subscription during October 9-November 6 through its branches nationwide.
Fitch Ratings (Thailand) earlier assigned "A+" for the issue. BAY earlier planned to raise only Bt12 billion, but decided later to increase the size to Bt20 billion.