In this paper we extend the work of robust trajectory tracking by guaranteeing hard error bounds for nonlinear systems with matched disturbances. A recently developed algorithm is extended in order to prove in case of bounded matched uncertainties maximum error bounds and furthermore to calculate them a priori. Additionally we discuss the specific problem of actuator uncertainties. It will be shown that even in case of actuator uncertainties and additionally matched disturbances it is possible to ensure robust tracking under guaranteed state error bounds. At the end a numerical example will verify the design procedure. ©2009 IEEE.