A system for communicating a multicast packet through a network switch fabric is described. The system receives the multicast packet at an input port of the network switch fabric, where the multicast packet is directed to multiple output ports, and where the network switch fabric has a virtual output queue (VOQ)-based architecture, in which each input port maintains a separate VOQ for unicast packets to each output port and one or more VOQs for multicast packets destined to multiple output ports. The system sends the multicast packet by inserting the multicast packet into the one or more VOQs associated with the multiple output ports, so that multicast packets are queued separately from unicast packets. Moreover, the system may optionally dynamically modify a number of the one or more VOQs for the multicast packets based on a number of multicast flows through the network switch fabric.