In the U.S., the retail sector is the largest employment sector, and the third largest category of employers in this category is apparel and accessories retail stores. Retail jobs require working in stores while standing for long periods, and working hours are often irregular, including holidays and weekends. This has resulted in a gradual turnover rate. The fashion retail industry's working environment and high rate of employee turnover may lead to short- and long-term negative organizational performance (Park and Shaw, 2013). However, little is known about fashion retail employees' behaviors and attitudes toward fashion business' organizational sustainability performance. Based on social exchange theory and on social and human capital theory (Leana and Van Buren, 1999; Shaw et al., 2005), this research was designed to investigate the internal and external antecedents of U.S. fashion retail employees' organizational citizenship behavior and its consequences on the triple bottom line of organizational sustainability performance. With regard to the method used in this study, Qualtrics collected a total of 309 responses, and a total of 278 responses being employed in the development of the measurement model and structural model for the proposed research questions. Ethical climate positively influenced organizational citizenship behavior, while job satisfaction negatively influenced turnover intention. Further, turnover intention showed negative effects on all three dimensions of organizational sustainability performance. Likewise, the three added paths for the relation between organizational citizenship behavior and each of the financial, social, and environmental dimensions of organizational sustainability performance were found to have positive effects. Through a social exchange between employees and organizations, when an organization provides an ethical working environment, employees may have lower turnover intention or may develop a higher level of organizational citizenship behavior. This has theoretical implications, suggesting that the two theories are helpful when explaining the role of employees' organizational citizenship behavior in organizations' overall sustainability performance. This implies that employees' positive attitudes toward their jobs are a central component of improving organizational sustainability performance. One effective way to increase job satisfaction is to listen thoughtfully to employees' ideas for job improvement, or their problems, concerns, frustrations, and conflicts.