Harmonic priming studies have shown that a musical context with its tonal center influences target chord processing. In comparison with targets following baseline contexts, which do not establish a specific tonal center, processing is facilitated for a strongly related target functioning as the tonic, but inhibited for unrelated (out-of-key) and less related (subdominant) targets. This study investigated cost and benefit patterns for the processing of the 3 most important chords of the harmonic hierarchy. Response time patterns reflected the chords' ranking: Processing was fastest for the tonic, followed by the dominant, and then the subdominant. The comparison with baseline contexts replicated the benefit of processing for tonic targets (Experiments 1 and 3) and the cost of processing for subdominant targets (Experiment 3), while dominant targets were situated at baseline level (Experiments 1 to 3). Findings indicate that listeners implicitly understand fine differences in tonal stabilities and confirm the special status of the tonic being the most expected and solely facilitated chord at the end of a tonal context. Findings are discussed with references to sensory and cognitive approaches of music perception. (Contains 7 footnotes, 5 figures, and 3 tables.)