Background: South Africa adopted the policy on inclusive education in 2001 that aimed at offering quality and equity in education to all learners, as well as addressing their diverse needs in the classrooms despite their differences. Mixed ability grouping is one of the commonly used classroom practices in the schools, but little is known on how it reflects on principles of inclusivity. Aim: The study aimed to explore how mixed ability grouping reflects on inclusivity as one of the commonly used classroom practices. Setting: This qualitative study embedded in descriptive phenomenology was carried out in six selected primary schools of Johannesburg's Metropolitan region of South Africa. Methods: Six participants and their classrooms were purposefully sampled, and data were collected through observations and in-depth interviews with each individual participant. Data were analysed thematically and the organisation of the emerging themes was informed by Florian and Black-Hawkins' model on inclusive pedagogy. Results: Findings of this study revealed that mixed ability grouping takes into account learners' levels of academic performance, gender parity, age of learners, as well as learners' backgrounds leading to diverse learners accepting one another in the classrooms. However, there are challenges in providing differentiated instruction, using appropriate teaching/learning media, and opportunities for individualised instruction according to learner needs. Conclusion: The study argues that for mixed ability grouping to be more inclusive, it has to provide for differentiated instruction within the same group setups, use teaching/learning media that are tailored to meet specific needs of individual learners, as well as offering individual instruction to learners who need it.