An important property of speech is that it explicitly conveys speaker’s identity. Although previous studies have shown that speaker’s identity affects semantic processing, the influence of speaker’s identity on grammatical processing is less clear. Here we investigate subject-verb agreement in Slovak, when the agreement depends on the speaker’s gender (as cued by his/her voice) compared to when it depends on the formal grammatical gender of the subject. We compared ERP responses to Slovak verbs disagreeing with the formally-marked subject’s gender (e.g., (the) mother-in-lawFEM *stoleMASC plums), and to verbs disagreeing with subject’s gender as conveyed by the speaker’s voice (e.g., IFEM *stoleMASC plums). The formally-marked subject and verb disagreement resulted in a P600 preceded by an anterior negativity. However, disagreement based on the speaker’s voice elicited a posterior negativity but no P600. We will discuss differences in checking or repair mechanisms of these two agreement types.