Americans generally may enter Japan for business or pleasure without a visa for up to 90 days. Travelers entering the country without a visa must have a return or onward ticket in their possession, proof of adequate funds for their stay, and be otherwise admissible under Japanese law. Extensions of the 90-day stay are normally not allowed, and no changes to status are permitted.
If you will be staying longer than 90 days, you must obtain an Alien Registration Card ("Gaikokujin Toroku Shomeisho"), available free of charge from the municipal office of the city or ward you are residing. You will need to take your passport and two photos of size 4.5 x 3.5 cm.
If you move from one residence in Japan to another, you are required to re-register within 14 days.
Carry your Alien Registration Card with you at all times. The Japanese Police are allowed to stop you and ask to see the card at any time, and not having it with you is a violation of local law.
If you are planning to stay in Japan more than 90 days, seek a change of status or perform tasks which do not fall under the definition of routine business, you should obtain a visa before coming to Japan. Visas are issued only by Japanese Embassies and Consulates overseas.
If you already have a Japanese visa and plan to leave the country temporarily for any purpose, make sure you get a re-entry permit in advance. There is a fee for the permit.
Please note that the Embassy has no authority to intervene in any Japanese government immigration decision.
General Consulates of Japan: