This application relates to the field of communication technologies, and discloses a communication method and apparatus. The method includes: After registering with a first network and a second network, a terminal device may send first information to a network device in the first network or a network device in the second network, so that the network device in the first network or the network device in the second network can learn that the terminal device is to enter a first transmission manner or has entered the first transmission manner. The first transmission manner includes: The terminal device concurrently processes an uplink service of the first network and an uplink service of the second network.