A filling material and method for reducing the amount of filling material required for filling a soft casing to a pre-selected specification, the filling material comprising a blend of polyester fibers having two or more different deniers and providing at least a 6% reduction in the amount of filling material required as compared to an alternative fill material consisting solely of polyester fibers of a single denier wherein the soft casing filled with the filling material meets pre-selected specifications comprising a pre-selected height measurement for the filled soft casing and is substantially the same in appearance as a soft casing filled with the alternative fill material consisting solely of polyester fibers of a single denier.