Originally Posted by
Majuki
The quoted DCC offer was $126.25 for 485.00 MYR at 3.83%. The posted transaction amount was $117.42, saving $8.83, which would have effectively been a 7.52% surcharge with DCC had I accepted the DCC offer. I don't know how the acquirers calculate the percentage since the exchange rate hasn't changed between the transaction time and the posting date. Chase uses the Visa exchange rate from the posting date of the transaction, the effective percentage could change if there's a material change in the exchange rate between the transaction date and the posting date for the transaction.
Merchants state that you will pay a certain fee on top of a reference rate, but the merchant sometimes chooses a reference rate which already contains an unspecified fee. Instead of trusting the merchant's quoted reference rate, always look up a reference rate yourself from a trusted source.