The present disclosure discloses example communications methods and apparatuses. One example method includes obtaining effective carrier indication information from a network device. An effective carrier frequency is obtained based on the effective carrier indication information, where the effective carrier indication information includes first information, second information, and third information. The first information includes first indication information, second indication information, or third indication information. The first indication information is used to indicate that carriers are not paired, the second indication information is used to indicate that carriers are paired, the third indication information is used to indicate a paired carrier frequency spacing, the second information is used to indicate a start carrier frequency, and the third information is used to indicate a frequency domain location of an effective carrier relative to a start carrier.