A lot of the company's business activities failed due to not adapting to user needs and technological developments. Previous studies show that there is no way to implement UX guidelines that explain the specific user needs for the UX of e-commerce systems. Therefore, we need a way of implementing UX for e-commerce websites. We used usability parameters in ISO 9241-11, namely effectiveness, efficiency, and satisfaction, to measure the system's usability and then conduct an interview to follow up the result. This research identifies how e-commerce companies implement UX best practices for their systems that can be used for other people who want to design their e-commerce applications.