This may not entirely be a currency conversion screw up, but it is possible. It often happens in the search engines. If you are buying a more expensive ticket $1000 or maybe even a $6000 business class ticket it is important to check on other websites.

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An airline like American Airlines will base its ticket prices on the US currency. Which means it would normally be cheaper to buy the ticket on their US site. However in the example on this page, if you had a European credit card, it would be cheaper to buy your ticket on the German site. Or if you had a Canadian or an Australian credit card it would also be cheaper to purchase on the German site. Watch the video to understand better.