The use of credit cards is widespread in Europe but may differ from country to country. The use of credit cards and other payment methods is more common in Western Europe. Countries like Denmark, the Netherlands and Germany might be an exception.
Denmark has its long tradition to only accept the pre-paid “Dan-card”, but its getting better. VISA is now accepted in a majority of the stores in Denmark.
In the Netherlands and Germany, cash is still king and the preferred payment method. Payment by credit card is accepted generally in global stores like McDonald’s and H&M. If you want to buy an ice cream or a hot dog, forget about it if you don’t have cash in your pockets.
Sweden is the number one country when it comes to the use of payment cards. More than 90 percent of buys are paid with cards. Some stores, don’t even accept cash longer and have signs that tells “no cash is handled”.
Also, parking och filling up your car at the gas station requires a card.
In Eastern Europe is cash payment totally dominating. Since decades of communism, people have a low trust in banks and want to “see” their funds. People in common does not prefer that you pay with a card. It’s accepted almost everywhere but is considered a little bit difficult.
If you plan to visit several countries in Europe at one time, I would recommend a steady sum of Euros, and a credit card with possibilities to withdraw at the airports. The Euros you could use for exchange to local currencies. If you can’t exchange, Euros is also a popular second currency due to the stable exchange rate.
One last thing. It is most simple to just bring your card and then withdraw Euros at an ATM. Check fee’s with your bank before departure.