A method of forming a higher density bale of waste paper from two or more lower density bales of waste paper includes positioning the lower density bales intact and in side-by-side relationship with respect to each other, moving them to a compression zone, and compressing the bales together in the compression zone to form a higher density bale. The higher density bale can then be strapped to maintain its higher density configuration and shape. Thus, a larger tonnage of waste paper in bales can be loaded into a shipping container for transport. A rebaler for carrying out the method includes side feed and side retrieval of bales, significantly improving over traditional top feed machines.