Marriage has undergone changes in its meanings, expectations, and patterns of formation under contemporary social conditions. In Iran, despite the continuing normative importance of marriage and family formation, increasing delays in marriage and growing reservations among some young people have made the meanings attributed to marriage an important subject of sociological inquiry. While previous studies have examined delayed marriage, marriage avoidance, changing attitudes toward marriage, and reflexive singlehood, less attention has been paid to how unmarried men themselves understand the meaning and nature of marriage, particularly men with relatively stable socioeconomic conditions. The present study therefore aimed to explore how unmarried urban middle-class men in Tehran understand marriage, how they interpret its nature and consequences, and how these meanings shape their assessment of marriage and its future. The study employed a qualitative approach and thematic analysis. Participants were 24 unmarried men aged 28–35 living in Tehran who were selected through purposive and snowball sampling. The study focused on men with relatively stable socioeconomic conditions, including educational attainment, stable employment, and home ownership, who nevertheless remained unmarried. Data were collected through semi-structured interviews addressing participants’ understandings of marriage, its nature and structure, responsibilities and expectations, perceived risks and concerns, and views about its future. The interviews were analyzed thematically until conceptual saturation was reached. The trustworthiness of the findings was strengthened through attention to credibility, transferability, dependability, and confirmability. The analysis generated one main category, three subcategories, and 11 concepts. The main category was “perceptions, attitudes, and outlooks of unmarried urban middle-class men toward marriage.” The first subcategory, “nature and structure of marriage,” included unequal exchange, asymmetric responsibility, restriction of freedom, temporariness and instability, marriage as a risky and troublesome decision, and “spouse as wallet.” Participants’ accounts indicated that some of them perceived marriage as involving an imbalance in rights, obligations, financial responsibilities, and personal freedom. “Unequal exchange” referred to perceived imbalance in responsibilities, rights, and expected benefits, while “spouse as wallet” represented participants’ perceptions of economic expectations attributed to women in marital relationships. The second subcategory, “concerns and anxieties about marriage,” consisted of fear of divorce, distrust toward a spouse or partner, and concern about children’s future. Thus, marriage was understood not only as a pathway to intimacy, companionship, and family formation but also as being associated with uncertainty, vulnerability, and anticipated consequences. The third subcategory, “the outlook and future of marriage,” reflected participants’ perceptions of declining formal marriage and the possible expansion of diverse forms of relationships outside formal marriage. These views represent participants’ perceptions rather than empirical predictions of future trends. Overall, the findings indicate that, for the participants, marriage has shifted from a largely taken-for-granted social expectation toward a conditional and reflexive choice. Relatively stable employment and housing did not automatically translate into willingness to marry; instead, marriage was evaluated in relation to autonomy, relationship quality, trust, security, responsibilities, and possible future consequences. The findings can be interpreted through perspectives on individualization, reflexive modernity, risk, and changing intimacy. Marriage increasingly becomes part of an individually constructed life trajectory rather than an unquestioned stage of the life course. The prominence of autonomy and concerns about restrictions on freedom is consistent with this transformation, while fear of divorce, distrust, and uncertainty indicate that potential negative consequences have become part of participants’ evaluations before entering marriage. At the same time, perceptions of unequal exchange and asymmetric responsibility suggest that gendered expectations remain an important dimension of how some participants interpret marriage. This finding also indicates that the transformation of marriage does not simply involve weakening attachment to the institution; rather, it involves a change in the criteria through which marriage is evaluated and accepted. In this context, expectations of reciprocity, trust, autonomy, and relational security become central to the assessment of marital commitment. The findings further suggest that economic stability alone is insufficient to explain marriage decisions among these participants, because the perceived quality and consequences of the marital relationship increasingly become part of the decision-making process. The central analytical contribution of the study is the connection of three dimensions that are often examined separately: the redefinition of marriage, the perception of risk, and the imagined future of marriage. The findings suggest that participants first reassess the nature and structure of marriage, then evaluate its potential costs, risks, and consequences, and finally reconsider the place of formal marriage in their future. Accordingly, marriage is not merely a delayed life event; its meaning itself is reconstructed through continuous reflection and evaluation. Remaining unmarried, therefore, cannot be understood solely through economic barriers or delayed marriage timing; for some participants, it may also reflect a critical reassessment of the institution itself and the conditions under which marriage is considered acceptable. The findings point to a process of individualization of choice, riskification of the marriage decision, and conditionalization of marriage acceptance. The findings should nevertheless be interpreted within the study boundaries, as the participants consisted of 24 unmarried men aged 28–35 from the urban middle-class context of Tehran and therefore cannot be statistically generalized to all unmarried men or middle-class groups in Iran. The study nevertheless provides an in-depth sociological interpretation of how a specific group of unmarried men constructs, evaluates, and negotiates the meaning of marriage under contemporary social conditions