The function of landscape corridors in terms of how characteristics such as width influence their usage by animals in a fragmented landscape has been a topic of considerable debate, restricted by lack of empirical data. This implies the need for further research, especially to generate data on mammal corridor usage, as mammals are the most sensitive to potential threats on a fragmented landscape scale. In the Mpumalanga Province in South Africa, the Mpumalanga Biodiversity Sector Plan (MBSP) was developed, containing a corridor connectivity map based on landscape features and electrical circuit theory. We aimed to resolve the lack of empirical data within the MBSP and investigated the number of mammal species and individuals that made use of these landscape corridors in a fragmented grassland ecosystem and if this was influenced by their width. Methods included ArcGIS analyses on structural corridor characteristics such as width and live trapping (using Sherman traps) of small mammals inside, outside and in the opening of corridors with widths of 100-200 m (narrow) , 200-300 m (medium) and 300-400 m (large). This research shows that the corridors in the province are actively used; significantly the most mammals were found inside the corridors. Species assemblages did not differ significantly. Preliminary results showed that corridor width is not a significant variable for either number of individuals and species. Even narrow corridors were shown to provide connectivity, but are thought to act as bottlenecks. Therefore, these corridors should be given priority for conservation planning in the developing landscape of Mpumalanga.