Osaka Central Post Office is at:
3-2-4 Umeda, Kita-ku,
Osaka-shi, Osaka-fu,
530-0001
If the above address is not good enough for you then it is located right near JR Osaka station. Postal windows at Osaka Central Post office are open at:
Mon. – Sun. 7:00 a.m. – 12 midnight
Post Office at Kansai Airport is open at: Mon. – Sun. 9:00 a.m. – 5:00 p.m.
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