An increase in the social unacceptability of smoking has dramatically decreased tobacco use in the USA. However, how policies (e.g., smoke free air laws) and social factors (e.g., social norms) drive the social unacceptability of tobacco use are not well understood. New research suggests that the stigmatization of smokers is an unrecognized force in the tobacco epidemic and could be one such mechanism. Thus, it is important to investigate the sources of smoker-related stigmatization as perceived by current and former smokers. In this study, we draw on the broader literature about stigma formation in the context of the tobacco epidemic and examine the role of attribution, fear, tobacco control policies, power and social norms in the formation of smoker-related stigma. We test hypotheses about the determinants of stigma using a population-based sample of 816 current and former smokers in New York City. The results show that perceptions of individual attributions for smoking behavior and fear about the health consequences of second hand smoke are important influences on smoker-related stigmatization. Structural forms of discrimination perpetrated against smokers and former smokers (e.g., company policies against hiring smokers) are also related to smoker-related stigma. Respondents with more education perceive more smoker-related stigma than respondents with less education and, Black and Latino respondents perceive less smoker-related stigma than White respondents. Social norms, specifically family and friends' expressed disapproval of smoking, contribute to the formation of smoker-related stigma. These findings suggest important points of leverage to harness the powerful role of stigma in the smoking epidemic and raise concerns about the possible role of stigma in the production of smoking disparities.