This study examines the effect of Social Media Marketing on Impulse Buying and investigates the moderating role of Financial Literacy among Generation Z in Denpasar City. A quantitative approach was employed, involving 100 respondents aged 20–29 years who reside in Denpasar City, are employed and/or have their own income, actively use social media, and have purchased fashion products through social media. Respondents were selected using non-probability sampling with a purposive sampling technique. Data were collected through a questionnaire and analyzed using Partial Least Squares–Structural Equation Modeling (PLS-SEM). The results indicate that Social Media Marketing has a positive and significant effect on Impulse Buying (β = 0.592, t = 6.629, p < 0.001). However, Financial Literacy does not significantly moderate this relationship (β = −0.055, t = 0.651, p = 0.515). The R-square value of 0.325 indicates that the model explains 32.5% of the variance in Impulse Buying. The findings contribute to understanding how digital marketing stimuli embedded in social media can shape spontaneous consumer responses in digital consumption environments. The insignificant moderating effect further suggests that financial literacy may not always function as an effective behavioral control mechanism when consumers are exposed to persuasive and emotionally engaging digital marketing stimuli. Practically, the findings highlight the importance of responsible digital marketing and financial literacy initiatives in encouraging more informed and sustainable consumption among young consumers.