BACKGROUND: Adherence to chronic medication is crucial for managing chronic diseases and preventing complications. However, maintaining consistent adherence remains challenging, particularly in low- and middle-income countries where forgetfulness is a common barrier. The widespread use of mobile phones, even in resource-limited settings, offers a practical opportunity to leverage inbuilt reminder features to support medication adherence. This study evaluates the effectiveness of inbuilt cell phone reminders in enhancing chronic medication compliance among patients in the eThekwini health district of KwaZulu-Natal, South Africa. METHODS: In this prospective, cross-sectional study, 400 patients on chronic medications were systematically selected from five healthcare centres. Participants were divided into two groups: those using mobile phone reminders (Group 1) and those who did not (Group 2). Medication adherence was assessed using a standardised questionnaire, and statistical analyses, including Chi-square tests and logistic regression, were conducted to identify differences in adherence rates. RESULTS: Group 1 exhibited significantly higher adherence rates (87%) compared to Group 2 (67%, p  0.001). The use of cell phone reminders was associated with a 2.5-fold increase in the odds of adherence (odds ratio [OR] = 2.5, 95% confidence interval [CI]: 1.7-3.6, p  0.001). CONCLUSION: Inbuilt cell phone reminders are a cost-effective intervention that significantly enhances medication adherence, especially in resource-limited settings. Integrating mobile technologies into public health strategies could improve chronic disease management.Contribution: This study highlights the potential of mobile phone reminders as a practical tool for improving medication adherence, with significant implications for public health strategies in low-resource settings.