This study investigates the factors influencing the success of e-commerce in the Southeast region, emphasizing the critical relationship between Electronic Word of Mouth, Personalization, Website Service Quality, and Customer Support Systems. Employing a quantitative research method, we collected 355 valid responses through an online survey targeting consumers engaged in online shopping. The data analysis, conducted using SmartPLS software, revealed that all hypotheses were statistically significant and positively correlated. Notably, Electronic Word of Mouth demonstrated the strongest impact on e-commerce success, followed by Personalization, Website Service Quality, and Customer Support Systems. These findings highlight the importance of enhancing customer experience through effective communication, personalized services, and attentive support, which are essential for fostering sustainable business practices. By implementing strategies such as leveraging Electronic Word of Mouth and optimizing website usability, businesses can not only improve their e-commerce performance but also contribute to long-term sustainability. Furthermore, this research encourages future studies to examine the interplay between new technologies, sustainable practices, and consumer behavior in e-commerce, thereby promoting a more sustainable future for the industry.