Vehicle roll stability is essential for safety and handling, especially during high-speed cornering or sudden lateral disturbances. This paper presents a comparative analysis of passive and active anti-roll bar (ARB) strategies using a yaw–roll vehicle dynamics model. A passive ARB serves as the baseline, while two active strategies—PID and LQR controllers—introduce controlled torque to counteract body roll. Time-domain simulations based on ISO 3888–2 double lane change were performed using a validated five-DOF model. Metrics include roll angle peak and RMS, as well as required actuator torque. Results show both active strategies improve stability over the passive ARB, with the LQR achieving the best trade-off between roll suppression and control effort. These findings support the use of model-based feedback control for advanced chassis systems.