Social media is one of the innovations which expands the option of web-based technologies to meet the needs of library users without access cost to them, and many public libraries in South Africa have embraced this technology. Against this backdrop, the purpose of the study was to examine the use of social media in the 8 public libraries in Mangaung Metropolitan Municipality in South Africa. Mixedmethods approach and a descriptive and case study research designs guided the study. Quantitative data was collected from 264 respondents using a questionnaire, and qualitative data from 16 library officials using an interview schedule. The study revealed that social media applications were used for conventional and web-based services such as Online Public Access Catalogue (WebOPAC), Prolib and Millennium Library Management System and free Internet access. However, lack of training activities, restrictive Wi-Fi access, low bandwidth, poor library officials’ attitudes and short time allocation to access the Wi-Fi make it difficult for the library users and officials to fully benefit from the web-based services available and offered by these libraries. Mangaung Metropolitan Municipality libraries should deliberately implement social media platforms, as this will contribute to how effectively their patrons can use and rely on their web-based services and other services. This study has implications to social media research, development and usage in public libraries.