This qualitative case study aims to investigate EFL learners' experiences in online autonomous learning as represented in their writing. The study explores characteristics that influence learners' writing and investigates how the writing product reflects their autonomy in learning. Purposeful sampling was used to choose twelve secondary pupils from an Indonesian private school. Data were gathered through semi-structured in-depth interviews, augmented with artifacts and student journals. Benson's (2012) aspects of autonomy used as a guide for thematic analysis. The participants' L2 writing experiences were observed while they were producing an academic essay. The study underlines the necessity of self-regulation and cognitive control during the writing process. The findings point to a multidimensional landscape shaped by technology, instructor feedback, and collaborative activities. Additionally, this practice, as seen by learners, not only improved overall learning quality by allowing them to focus on specific language components, but it also contributed to increased EFL writing confidence. Finally, teachers who want to empower students and improve language acquisition should recognize the importance and potential benefits of online autonomous learning.