Abstract: The examination of fast ion behavior in 3D magnetic fields is of growing importance in fusion scenarios. In addition to applied 3D perturbations in the tokamak and the inherently 3D stellarator equilibrium, the RFP possesses the unique ability to spontaneously change from a 2D-axisymmetric equilibrium to a 3D-helical equilibrium known as quasi-single helicity. A helical axis forms when the innermost resonant tearing mode grows to an amplitude large enough to envelop the magnetic axis while the subdominant modes decrease in amplitude. The helical core results in a local reduction of the tearing-mode induced magnetic stochasticity characteristic of the standard RFP. Prior studies have shown that a strong thermal transport barrier develops. This work presents the first comprehensive study of fast ion behavior in this state. An investigation of fast ion transport due to energetic particle-driven Alfvénic instabilities, tearing-mode induced stochasticity, and neoclassical effects will be discussed.