Various approaches to performing non-divergent parallel traversal operations for a bounding volume hierarchy (“BVH”) during ray tracing are presented. For example, a computer system has a processing unit with threads that, collectively, perform ray tracing for a group of rays in parallel in a computer-represented environment, which includes geometric objects (such as triangles) enclosed in the BVH. Each of the threads receives parameters for a given ray and traverses the BVH to determine an intersection, if any, between the given ray and one of the geometric objects. The order of traversal of the BVH is synchronized between threads for the rays of the group, for example, using a cross-group operation such as a ballot operation. In this way, the overall speed of the BVH traversal can be improved in many cases, while avoiding code divergence and data divergence in extra-wide single-instruction, multiple data (“SIMD”) graphics processing unit (“GPU”) architectures.