Performance based financing (PBF) has been increasingly implemented across low and middle income countries, including in fragile and humanitarian settings, which present specific features likely to require adaptation and to influence implementation of any health financing programme. However, the literature has been surprisingly thin in the discussion of how PBF has been adapted to different contexts, and in turn how different contexts may influence PBF. With case studies from three humanitarian settings (northern Nigeria, Central African Republic and South Kivu in the Democratic Republic of Congo), we examine why and how PBF has emerged and has been adapted to those unsettled and dynamic contexts, what the opportunities and challenges have been, and what lessons can be drawn.