The Industrial Revolution 4.0 and the recent Covid-19 pandemic has further boosted e-commerce activities worldwide, including Malaysia. Past studies have been inconclusive in explaining the ideal factors which underlie the intention of buying fashionable apparel via online platform. Thus, this study investigates as to whether apparel characteristics, platform features, and promotion have a significant positive influence on the intention to buy fashionable apparel via online platforms. A total of 306 samples were collected among Malaysian adult consumers. The results of the analysis showed that apparel characteristics impose the strongest positive influence on the intention to buy fashionable apparel via online platforms, followed by platform features and promotion. The study enriches the body of knowledge by demonstrating the impact of the underlying factors in determining the intention to buy fashionable apparel via online platforms based on the Theory of Planned Behavior. The practical implications reveal that marketers should enhance the characteristic of apparel available online, the features of the online platforms used and the promotional price of their online deals. Limitations and suggestions for future studies are also presented.