Samsung Galaxy S6 edge Instruction Manual page 458

Making a call from the other party
■ To have the other party in Japan call you
overseas
Have the other party dial a phone number in
the same way as in Japan.
■ To have the other party make a call from
outside Japan to the country you stay
Regardless of countries, you will receive a call
via Japan. The other party should dial with
prefix an international access code and "81"
(Country code of Japan).
International access code of the country the
dialer stays -81-90 (or 80, 70) -XXXX-XXXX
International roaming
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