We investigated the nonpolar surfaces in hexagonal 2H-, 4H- and GH-SIC using a density-functional-theory based tight-binding method (DFTB). In contrast to the surfaces in 2H-SiC, the clean ideal (1010)-surfaces in 4H- and GH-SIC, which probably occur e.g. at the walls of micropipes, turn out to be non-planar in 4H and 6H. The (1120)-surfaces, however, turn out to be similarly smooth in 4H- and GH-SIC as it is in 2H. The surfaces can be stabilised by simple adstructures.