I have that same size foot and ride this board in the regular width in a 156cm which has a 255mm waist width on it. So he will be just fine on the regular width board.

How tall is he?

get the regular...if you get the narrow...your probably going to get toe drag with a 9.5 boot

Kayla, I have a size 9 Burton boot and just threw my binders on this board (156 standard width) the other day. It seems that there are gonna be NO problems with drag for me, and I assume your BF will be the same. Also, since board length is alot about preference and riding style as well as physical size and weight I would try to sneak a peek at his current board to see how long you want to get it (the size is often printed somewhere on the board top and will probably just be a number between 150-160). If everything goes wrong and he gets mad at you for getting him the wrong size and you live in the Salt Lake area then dump him and give me a call. A girl who gets me a new snowboard for my birthday couldnt get me the wrong size if they tried.