I created an End of Month report that has many matrixes, graphs and tablixes in SSRS 200R2. Matrixes tend to produce a blank page(s) when previewed in a print layout. This is a very annoying experience for report developer.
It requires a bit of trial and error to remove the blank pages from matrixes. The trick is to contain the matrix in a rectangle and tick off the “Keep contents together on a single page, if possible” option from the rectangle. Then ensure that the size of the rectangle is within the size of the matrix with no white spaces. Then try to reduce the size of the row group column and/or the colum group columns and followed by resizing the body width. Keep doing this till it stops producing blank pages.
The following blog is very useful.
http://snippetsandhelp.blogspot.com.au/2012/01/ssrs-removing-blank-pages-in-your.html