Here are some figures on transaction costs in cross-border transactions. Currently the de-facto reference currency in cross-border transactions is the USD. A recent purchase of USD186 using the credit card resulted in the following line items in AUD: AUD (from USD) - $202.00 Currency conversion assessment fee: $0.40 International transaction fee: $3.00 Cross border assessment fee: $1.60 Ignoring the spread used in the currency conversion, the transaction cost is about 2.5%. The actual transaction cost taking the spread into account is probably about 3+% A recent purchase of USD700 using PayPal incurred a fee of $23 (buyer or seller pays). The transaction cost is a whooping 3.3%. I happened to have some USD in my account, so I didn't need to perform currency conversion. PayPal's spread in forex rate is notoriously poor compared to other avenues. A purchase of 1.45BTC (approximately USD1085 at that time) incurred a transaction fee of 0.0002BTC, which is negligible.