Mail Forwarding (転送"Tenso")

If you are new to living in Japan, have recently moved, or are planning to move in the near future, and want mail that is addressed to you delivered without a hitch – you should notify the post office about your new address.

To do this, fill out a “tenkyo todoke” (転居届) postcard and either hand it in at a post office or drop it into a mail box (just like any other letter)- no stamp is required.

Tenkyo todoke are available at post offices across Japan. There is also an online version on the post office website - http://welcometown.post.japanpost.jp/etn/ (in Japanese) - a credit card is needed to confirm your identity.

You can ask for a 'change of address notice' at any post office in Japan.
"Ten-kyo 　To-do-ke 　wo　 ku-da-sai"
転居届を下さい