We propose a new technique to stabilize spin orbit torque (SOT) magnetization switching with perpendicular magnetization anisotropy (PMA). Although SOT switching with PMA is attractive for high-speed and long-retention applications, high bias field is necessary for a deterministic switching. In this study, we investigate a low bias field effect on the SOT switching with PMA by means of micromagnetic simulations, and demonstrate a stable and fast magnetization switching assisted by canted magnetic fields.