If you’re traveling to the UK for example, you may be tempted to use your La Caixa Visa card, since, according the contract there is no fee for this. Unfortunately, they end up just ripping you off on the exchange rate, giving you a rate about 5% below the interbank rate.
Effectively you’re getting charged a 5% fee, but you might not know it unless you look up the historical exchange rates.
We also used a Deutsche Bank Visa, which looks like it charges a hidden 2% fee via the exchange rate.
If anyone knows of a Spanish Visa card that does not rip you off in this way, I’d love to hear it.
One alternative is an American Express Corporate Card, which doesn’t change any extras (at least with the contract my company has), but you can’t use it everywhere.