I came across this issue (I know this thread is old) when designing a report.
I'm using SSRS 2008. I had 2 matrices in the body of my report and the report was inserting page breaks in between the 2 tables. To fix, I dropped a rectangle from my toolbox onto the body of my report,; copied and pasted the 2 matrices into the rectangle, and set the page break properties of the rectangle to false. Now everything is on 1 page.