For the past 18 months I have been using the AEON ATM machines to make withdrawals from my US bank account. I have never been charged the standard 150 baht fee on this end that other bank ATM's take, and the exchange rate has always been better than the average rate for all the banks as listed on the following link (the TT rate is the same as ATM rate on this site):
http://bankexchangerates.daytodaydata.net/default.aspx
However, today when I made a withdrawal I went to my computer and saw that the exchange rate given was 10 satang lower than the bank averages. It's not a big deal...only a 200 baht loss, but it made me wonder if ATM transaction exchange rates are updated as often during the day as the rates at a walk-in local bank. Or perhaps AEON has decided that they will now give a less favorable exchange rate in lieu of charging the standard 150 baht fee.
Does anyone out there have any specific knowledge of how that process works with the ATM's so far as the timing for updating exchange rate fluctuations?







