All Thai bank ATMs charge the same 250 baht fee per withdrawal. Just be sure to decline the ATM's offered convenience conversion rate, and let your own bank do the conversion instead, which will always be at the much better official rate. The maximum withdrawal amount per transaction is
*****
to
*****
baht depending on the bank. Krungsri Bank (yellow ATMs) and Kasikorn Bank (green ATMs) allow
*****
baht.