The Region of Waterloo, Ontario, is a rapidly-growing metropolitan area approximately 100 km west of Toronto. In 2005, the Region’s transit operator, Grand River Transit, introduced an express bus service, known as iXpress, along the central northsouth corridor of the Region. This paper explores the impact of the iXpress service on transit user costs and passenger attraction. We employ a methodology to quantify the generalized cost (including waiting time, in-vehicle and transfer times) of transit trips between key destinations in the Region before and after the implementation of iXpress. We also develop a methodology to identify those customers who benefit from the reduced cost of the iXpress. Finally, we present the change in ridership (boardings) in the corridor pre- and post-implementation. From these demand and cost data, we compute transit elasticity of demand with respect to generalized cost.