Communications Communications Postal Services Letters and Postcards One 80 postage stamp is enough for all domestic letters weighing up to 25 grams.
Envelopes are available at stationery stores.
The sender is requested to affix the stamp to the upper left-hand corner of the envelope and write the address in legible Roman characters. The sender's name should be written on the reverse side of the envelope. Postcards are available at 50 and can be sent to any place in Japan. The cheapest rate for express mail is 270 for letters and postcards weighing up to 250 grams. All rates are calculated according to weight.