To enable operation with both three-phase and single-phase power grid, three-phase (3-ph) four-wire power factor correction rectifiers (PFCs) are widely used for on-board chargers. Conventionally, the PFC rectifier is regulated with three independent boost modes for the three-phase operation, while with totem-pole mode for the single-phase (1-ph) one. The control structure for the 1-ph/3-ph are different, which leads to additional effort for the control design. In this work, a universal control strategy enabling 1-ph/3-ph operations for three-phase four-wire PFC rectifiers is proposed. When switching to the single-phase operation, the third phase is modulated with the switching frequency, which is able to regulate the current distribution between the phase and neutral line. As a result, the current stress on the cables and power devices can be balanced, leading to a more efficient design. Besides, the voltage feedforward and deadtime compensation are also considered to improve the dynamics and increase the input power quality. Finally, the feasibility of the proposed control strategy is verified by simulation.