This study focuses on developing digital patient portals to support chronic disease self-management in primary care settings of Zimbabwean and Comoros contexts. A mixed-methods approach was employed, including qualitative interviews (n=30) supplemented by quantitative usability testing (n=50). Participants reported high satisfaction with the digital portals' user interface design, with a mean score of 8.2 out of 10 for ease of use and accessibility. The digital patient portals were found to be effective in enhancing chronic disease self-management practices among participants. Further research should investigate long-term effectiveness and potential scalability of these digital solutions. digital health, chronic diseases, usability testing, user interface design, primary care