Despite the growing interest in the field of religious peacebuilding in the last two decades, the role of religion in peacebuilding is yet to be mainstreamed. Evaluation of peace-building success has been identified as one of the major challenges facing the field in the twenty-first century. Using the cities of Jos and Kaduna in northern Nigeria, in which major religions have significantly contributed to peacebuilding, as case studies, this study explores the factors that explain the success of faith-based post-conflict peacebuilding in these two cities between 2000 and 2015. The multi-faith approach, pacifist strategy, grass-roots peacebuilding, and commitment were outstanding in the success of faith-based peacebuilding in the two cities. These achievements support the growing evidence that bottom-up approaches as well as collaborative strategies are key strengths of faith-based peacebuilding.