Singleness for women beyond the age considered conventional for marriage is regarded as a misnomer in Nigeria. Such women are pitied and blamed for their status. Often the blame is based on assumed personal character defect of the women. Nevertheless, empirical research by some sociologists and other women scholars has linked singlehood to demographic, economic, religious, and personal causative factors. Building on these past studies, this article employed aspects of Silvia Walby’s "theorising patriarchy" to examine patriarchy, a structural determinant of singlehood that has not received much attention in the study of singlehood in Nigeria. Twenty-nine involuntary, childless, never-married women aged 30 to 48 years were interviewed in urban Lagos, Nigeria. The women’s narratives revealed the limiting effects of the six patriarchal structures identified by Walby in their opportunities to marry. This study provides relevant information for attainment of Nigeria’s gender policy and contributes to intercultural understanding of singlehood.