A method using classical mechanics to identify exact resonance eigenstates of a reactive scattering system is presented. Semiclassical approximate eigenstates are first constructed from classical trajectories of a defining topology. The semiclassical wave functions then serve as initial states for an exact quantum time‐dependent wave packet propagation. The quality of the initial semiclassical approximation is readily apparent from the extent to which the spectrum of the resulting dynamics is dominated by a single peak. The systematic construction of the resonant eigenstate spectrum in association with a progression through defining classical topologies is emphasized, and the predictive implications of the method for approximating essential resonant eigenstate nodal structure and energies are discussed.