Originally Posted by
themicah
I charged 28.85 GBP to my Schwab card on 2/5/09. Almost immediately an authorization showed up for $40.50 (give or take a few cents--it was definitely under $41). This morning Schwab is showing a charge for $42.97.
That's a big difference. There has also been a lot of volatility in the currency markets in the last several days. Oanda.com shows a 3% difference in the interbank GBP/USD rate between 2/5 and 2/10, so that would account for some of the difference, but not all.
Credit card transactions post at an exchange rate based on the posting date (often the close of business the day before). The authorization was probably based on close of business 2/4/09.
Oanda.com:
2/4/09-->41.17USD
2/10/09-->42.82USD
I suspect this difference is entirely the result of Fx market fluctuations.