flying to Japan without return ticket?

I plan to visit Osaka and maybe Kyoto pretty soon. I am a US citizen and plan to stay in Japan for 3 weeks at most. Since I'm not sure when I'll leave, I don't want to buy a return ticket yet. But I've heard they will be checked by the AIRLINES before they let me board the plane to Japan.

If I don't have one, would it suffice if I just TELL THEM that I plan to take the ferry from Fukuoka to Busan? Or do I have to show them the printed out ticket of it? Anyone know of any websites where I can purchase the refundable ferry tickets from Japan to Korea?

You might be better purchasing a open return ticket. Several years ago I bought a simgle ticket as id just got married to a Japanese and was planning not to return to my country for more than a year. At the airport the airline would not let me board even after showing my marriage certificate and husbands passport. They wouldn't budge. I had to buy a return portion there and then and it cost an absolute fortune, I also very nearly missed the flight. I really wouldn't advise it! Good luck

You can tell them anything but they might not let you board. Even if you get on the plane, a passenger with a one way ticket raises a red flag immediately, so you'll be grilled at immigration. In worst case scenario, you'll be denied entry. Don't take the chance. Buy a return trip ticket with the open return date.

You could buy an additional fully-refundable one way ticket for the return. Then once in Japan cancel that ticket and get your money back with no penalty. It's a pretty silly rule, because it's so easy to get round and as discount return tickets are often much cheaper than one way - if people planned to overstay, they could just buy a return ticket and throw away the second journey.

As listed on the US Embassy site for Japan (but applicable to other western nations as well):

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.

Going to the airport with a one-way ticket and no visa is almost always denied boarding.
You might get through with a one-way and a promise, but someone with the identical situation could be refused entry by Japanese Immigration. Remember, there is no guarantee Japan will allow you into the country!

Airlines are fined megabucks for bringing in someone who then gets sent back. So they do function as a de facto gatekeeper. More than likely you will be denied boarding at your airport of departure unless you buy a return or onward ticket at the airport (very expensive). It would be wiser to get an air ticket with a cheap or free date change ability, or have an onward ticket by plane/ship/ferry etc to show. It'd be a real drag after a nightmarishly long airplane ride to be told your vacation plans are DOA.

I am in Hong Kong now. I want to fly to Japan and then Korea and then back home to the USA. Since I'm fairly sure when I want to return to the US, if I show them my online reservation for a flight from Korea to the US, would I be allowed to enter Japan? Would I still be required to show a ticket from Japan to Korea?

I'm also thinking about just flying to Korea first and then going to Japan by ferry instead. That's because I don't think I would be required to have a return ticket in order to enter Korea. To enter Japan this way, would just showing them my online itinerary for a flight from Japan to the USA suffice? Or do they need to see the actual flight ticket?

Also, is it ok if my ticket to Korea is for a ferry instead of an airline flight? Do they have to see the actual ticket or would showing them my online reservation suffice?