Abstract: Embodiments of the present disclosure generally pertain to systems and methods for controlling multicast bandwidth. A communication system in accordance with an exemplary embodiment of the present disclosure comprises a network access device (NAD) having bandwidth (BW) expansion logic. The BW expansion logic is configured to automatically calculate the expansion ratio for a multicast stream based on various network parameters, such as layer 1 and 2 information, network packet size, and network transmission rate. Based on the expansion ratio, the BW expansion logic determines the actual transmission rate for transmitting the multicast stream across a subscriber link. The NAD then accepts or rejects join requests based on whether the sum of the current allocated link rate and the actual transmission rate exceed a rate threshold for the link.