Techniques are provided to enable group addressing for multicast transmissions in a frame that is configured to support multi-user transmissions. The frame comprises a header field that is configured to indicate to recipient devices associated with a multi-user transmission interval during which time, frequency and spatial channel resources are allocated to allow for the transmission of a data frame or simultaneous transmission of corresponding ones of a plurality of data frames to respective recipient devices. In the header field, group identification information is wirelessly transmitted that indicates a group of recipient devices which are to receive a transmission during the multi-user transmission interval. Data is wirelessly transmitted for a multicast transmission during the multi-user transmission interval that follows the header field, where the multicast transmission is intended for a group of recipient devices that are members of a multicast group corresponding to group identification information contained in the header field.