Aim: To highlight the possibility of synchronous benign and malignant nasal masses. Schneiderian papilloma, also known as inverted papilloma, despite being a common benign epithelial sinonasal tumour, remains a conundrum to otorhinolaryngologists due to its locally aggressive nature, tendency to recur as well as potential of malignant transformation. A synchronous nasal lesion adds on to the complexity of patient management. Case presentation: Herein, we are reporting an unusual case of synchronous lesions: sinonasal inverted papilloma and low-grade mucoepidermoid carcinoma. Initial biopsy of the sinonasal mass revealed inverted papilloma. However, histopathological examination post endoscopic medial maxillectomy revealed evidence of both inverted papilloma and low-grade mucoepidermoid carcinoma. Conclusion: We want to highlight that seemingly benign sinonasal inverted papillomas ought to be taken seriously considering the possibility of a synchronous malignant nasal mass, as in our case.