Instead, for large foreign transfers (say, 50,000 CZK), I´d recommend a specialty foreign exchange center – NOT one of the foreign exchange stands that flood the streets of Prague 1, but an actual, official, exchange center, such as Aktiv Change. Just be careful with them as well, because you´ll need to change a certain amount of money to get the best rates (usually 50,000 CZK; 30,000 CZK for Aktiv Change). For transfers under this amount, if at all possible, I´d recommend using an ATM (bankomat) – this means, of course, you´d have to be taking the money out of your own foreign account using some kind of debit or ATM card. ATM rates are known to constantly fluctuate (and can´t always be verified ahead of time), but they are set to an international standard by the card issuers, and should be among the best rates available; you´ll have to pay a fee for using the ATM, but no commission, and you´ll immediately have the cash – which you can then deposit at your bank. For a small fee, of course.