I select Mastercard because it is easy to compare credits cards between the following countries.
Finland Nordea Mastercard Silver 3 month euribor + 8.5% Estonia Nordea Mastercard Standard 18% Norway Nordea Mastercard 19.5% p.a. while effective with e-bill (which you have to have) 24.87%
Confusion previously in interest-free days
Banks of Nordea Finland, Estonia and Norway advertise their similar cards differently. Bank Estoinia and Norway say you get "maximum 45 days interest-free time", while Nordea Finland says you get "on average 30 days interest-free time". In each bank, you can pay your shoppings at 15th of the next month so you get 45 days maximum in each bank if you buy your shoppings at 1. day of the month.
So the best way is to get credit cards from Norway (NOK) and Finland (EUR), since you get lowest interest rates there.
Assume that you want to pay always your bills before you must pay the interest.
I think the current interest of Mastercard in Finland is about 8.8%, while in Norway for the same card 24.8%.
Why is the interest so much lower in Finland than in Norway?