Background: Two intervention approaches are implemented in South Africa to alleviate the deleterious consequences of congenital or early onset hearing impairment on language acquisition and subsequent poor learning outcomes. Aim: This study investigated the learning outcomes of foundation phase learners with severe to profound hearing impairment who received Listening and Spoken Language -- South Africa (LSL-SA) (adapted Auditory Verbal Therapy) therapy compared to those who received Traditional Speech-Language Therapy (TSLT). Setting: The study was conducted at four early intervention (EI) schools for children with hearing impairment across three provinces in South Africa. Methods: Data were collected through record reviews of their Speech-Language Therapy Outcomes and South African National Department of Basic Education academic report cards. Data were analysed using quantitative statistics. Results: Findings demonstrated that children with hearing impairment enrolled in LSL-SA outperformed those enrolled in TSLT in achieving age-equivalent language outcomes. A higher percentage of learners enrolled in LSL-SA achieved meritorious to outstanding learning outcomes. While a comparable number of learners progressed to mainstream schooling, children with hearing impairment enrolled in LSL-SA are enrolled for a shorter duration until discharge than those enrolled in TSLT. This is an important finding, particularly in low-middle income countries (LMICs). Conclusion: Listening and Spoken Language -- South Africa graduates achieved superior learning outcomes dependent on language attainment, providing contextually relevant evidence supporting the effectiveness of the LSL-SA EI approach. Contribution: These context-specific outcomes stress the obligation to upscale and fast-track EI services. Implications for investment in LSL-SA are proposed through collaboration between families, educators, and early interventionists.