A system and method for multicast routing using peer groups includes a router. The router includes a control unit and a memory coupled to the control unit. The memory stores one or more first multicast routing entries. The control unit is configured to receive a multicast packet on an input interface, determine one or more properties of the multicast packet, determine one or more output interfaces based on the properties and the first multicast routing entries, and forward copies of the multicast packet on each of the output interfaces. The router is configured to be coupled to a peer router via an inter-chassis link (ICL). The first multicast routing entries include one or more second multicast routing entries associated with multicast routing trees associated with the router and one or more third multicast routing entries associated with multicast routing trees associated with the peer router.