A method performed by a user equipment (UE) in a wireless communication system is provided. The method includes transmitting, to a base station, capability information of the UE, and receiving configuration information associated with a transport block size (TBS). The TBS is determined based on a value of NRE·R·Qm·v. The NRE corresponds to a number of allocated resource elements, the R corresponds to a code rate, and the Qm corresponds to a modulation order, and the v corresponds to a number of allocated layers. A maximum value of the TBS is considered for transport block over multiple slots (TBoMS), and the maximum value of the TBS is determined by limiting at least one of a value of the NRE, the R, the Qm, or the v.