The growing utilization and effectiveness of social media in marketing has captured the attention of both academic researchers and industry practitioners. Therefore, the purpose of this study is to test a social media marketing model within the fashion and apparel industry. This research is applied in nature and descriptive-survey in terms of data collection methodology. The research strategy employs structural equation modeling. The statistical population consists of managers of large-scale fashion and apparel businesses in Iran. Given the large (effectively infinite) population size, the sample size was determined using Cochran’s formula, resulting in 385 participants selected through convenience sampling. Data were collected using a researcher-developed questionnaire, whose face validity, content validity, construct validity, and reliability were calculated and confirmed. Data analysis was conducted using SPSS 22 and SmartPLS 4 software. The findings indicate that all indicators and factors exhibit factor loadings greater than 0.4, confirming the validity of the proposed indicators and constructs. Furthermore, the causal factors significantly influence the social media marketing model in the fashion and apparel industry, while contextual and mediating factors significantly affect marketing strategies. Additionally, the strategies demonstrate a positive and significant impact on outcomes. Finally, the results confirm that the proposed model exhibits an appropriate fit.