Bangkok Bank, and as far as I know every Thai bank, charges an incoming Swift wire transfer fee. Bangkok Bank has a minimum and maximum charge of 200 to 500 baht. The outgoing Swift wire charge depends on your bank. With Fidelity it is always free. If your outgoing fee is 0 (or another small fixed amount), because of the
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BB charge, small transfers will generally be cheaper with Wise, whereas larger ones, after you hit the 500 baht cap, will be better using Swift, since you will asymptomatically approach the TT rate which is generally better than Wise's *effective* rate (i.e after their charges have been factored in).