Booking a Ryokan

I've been looking at quite a few websites for ryokans, and most of the sites have several options, such as 2 person, 3 person, or 4+ person.
What I'm not sure of, is whether they will allow one person to book a 2 person room (ie. the smallest available) and only have one person stay there. I would assume this isn't a problem because in the end you're paying for two people but just using it as a single room and not the other way around where you're trying to rip the owners off by underbooking a room...
Some clarification on this would be great though, thanks.

It depends on the individual ryokan. You will have to inquire directly in each case.

A few ryokan are unflexible and will simply not sell a room to a single person even if they are completely empty.

More commonly, ryokan which do not officially advertise room rates for single occupancy are flexible and will sell their rooms also to single guests. The per-person price will usually be higher than in case of double occupancy. In the worst case, you pay have to pay for two.

Last but not least, there are ryokan that officially have rates for single occupancy and do even advertise stay plans for single travelers.

Alright, thanks. I was looking more specifically at this site: http://www.kurama-onsen.co.jp/plan02_e/index.html it says ''rooms for 2 people or less'' but what I've seen on a few other sites is that you still pay for two people, ie. double the price listed there. However since they list ''or less than 2 people'' I wonder if 1 person would pay the same rate...

For single travelers, they will *probably* not charge you double - you are not going to eat meals for two people :)

Their reservation website does allow the users to specify "one adult" in a room, so I think you can just go ahead and book, and see if they come back with any "single occupancy" charge on top of the price listed. Since they say "starting from 17,850 yen" (that's what the "-" is supposed to mean; I checked on the Japanese page), I expect them to get back to you with the charge for that specific day you reserve.

Or you could inquire in advance by e-mail, giving them the date and asking for the charge (from "Contact Us").

http://www.japaneseguesthouses.com/index.htm

is my fave site for finding ryokan accomodation. And they will have information about each Ryokan, ie if they accept Single Guests.