Perceptual regularities have been investigated intensely in music research but to a lesser extent in speech research possibly because of its irregular nature. People tend to rhythmize almost every given acoustic input though, even if one stimulus is physically identical to the next. Hence, perception of regularities seems to be highly subjective, and may not solely be driven by acoustic cues. Using event-related potentials, we show that participants perceive regularities in speech and register even subtle deviations in trochaic speech patterns (‘Gina ‘hätte ‘Norbert ‘gestern ‘abend ‘küssen/*be’lohnen ‘sollen; Gina should have kissed/rewarded Norbert yesterday evening). This is evidenced in a P600 response that varies as a function of task. Our results provide evidence for attention-dependent perceptual regularity in speech.