Originally Posted by
HawaiiO
In my experience, cash is king in Japan and tons of places do not accept MC/VISA/AMEX.
Train stations, restaurants, smaller hotels, places like that.
Be sure to have back up cash and check beforehand if the location accepts CC.
Also some ATMs there do not take our US cards for withdrawing cash.
It's more than "some." It's most. Your U.S. card is most likely to work at a post office or Citibank ATM.
Also, if you need to get a cash advance on a credit card (not recommended except in emergencies, due to the high and separate interest rates), just walk into any bank that displays your card's logo and ask for "cashing" (
kyashingu). You must know your card's PIN, though.