A circuit switched fallback (CSFB) method and apparatus, where a user equipment (UE) initiates a calling process, receives a first request from a first communications system, and after the UE is transferred to a second communications system and before the UE receives a first message from the second communications system, the UE determines that a voice call bearer cannot be set up in the second communications system, and initiates a CSFB in the second communications system, where the first message is used by the UE to determine that a call request has failed.