A few years ago, they passed a law that if you are a foreigner, you must show a work permit to open a bank account. (Don't know about people on retirement visas.) In fact, I went to the bank for an existing bank account opened way before that law, and all I wanted was to register it so I could use the website for my account -- the staff would not do it, told me that I needed a work permit.
At another bank, their solution was if I were married (to a Thai), the Thai person could open it in their name for me, which is not a great solution.
Is it still the same? Or can you open a bank account there now without a work permit?