So, although you should use common sense, it's a good idea to exchange enough cash before you head out of major metropolitan areas. Credit Cards, ATM's and Wiring Money Major credit cards are accepted at large hotels, restaurants, shops and many other places, but Japan still remains a cash society. It's always best to ask first if you don't see a sign by the door or cash register, and even if you do see the sign, some places will only take locally issued credit cards. The most commonly used cards are Visa and American Express, and to a lesser extent, Master Card and Diners Club. Cash advances are possible, though it is often hard to find a bank that will do it.
Most people think of Japan as a modern and hi-tech country, and in many ways it is.
However the banking system isn't one of them. ATM's are now widespread, but have limited hours and are sometimes closed on Sundays and National Holidays. Generally they are open from 9am to 7pm on weekdays and 9am to 5pm on weekends. In big cities and commercial districts you can often find ones that are open later and on holidays. It is possible to have money wired to you in Japan, but you will need to know the bank, the branch and the exact location.