This study aimed to examine the effectiveness of using online task-based learning to improve the EFL speaking skills of Nigerian secondary stage students. The study used a quasi-experimental design to investigate the effects of online task-based learning. Fifty (50) students were chosen to participate in the research. Both experimental and control groups consisted of intact classes of twenty-five (25) students. A self-developed instrument titled "EFL Speaking Skills Test" was administered to determine the pretest and post-test performance of the two groups. The data were analysed with a t-test for independent samples. Students' EFL speaking skills have improved as a result of using online task-based learning. It was recommended that the government should ensure adequate provision of teaching and learning facilities such as ICT-integrated classrooms, learner-friendly spaces, premium subscriptions to LMS suites, and adequate provision of networks and internet in schools in order to facilitate smooth interactions between teachers and students. The teachers' capacity for task-based learning should also be enhanced, along with their ability to effectively utilise online resources. Keywords: Online Task-Based Learning, EFL Speaking Skills, Task-Based Speaking & Nigeria