Irony comprehension requires going beyond literal meaning to infer a speaker’s dissociative stance. Pragmatic accounts propose that this entails evaluating a speaker’s vigilance towards the falsity or irrelevance of the literal proposition, a cognitively demanding process even for adults. Yet, previous research often presupposes successful irony comprehension, focusing on processing measures rather than directly testing interpretive accuracy. This study adopts a theory-driven approach by manipulating speaker cues as pragmatic markers of epistemic vigilance and assessing their impact on irony processing and comprehension. Participants read vignettes with ironical or literal utterances produced by speakers described as epistemically vigilant or non-vigilant. Online processing was assessed through reading times, while irony understanding was measured with polar questions probing interpretations of the speaker’s belief and communicative intent. Results showed that participants often misinterpreted ironical statements but were significantly more accurate when speakers were described as vigilant, indicating that speaker-based epistemic cues guide pragmatic interpretation. This effect emerged in comprehension but not in online processing, suggesting that evaluations of speaker intent occur later during more reflective stages of interpretation. These findings underscore the interpretive complexity of irony, challenge assumptions about its automatic understanding in adults, and highlight the socially situated nature of pragmatic inference, with implications for theories of communication and language processing.