This disclosure provides methods, devices and systems for communicating over multiple links, for example, indicating buffered units (BUs) per traffic identifier (TID) for transmission to multi-link devices (MLDs). One innovative aspect of the subject matter described in this disclosure can be implemented in a method for wireless communication. The method can be performed, for example, by a non-access point (non-AP) MLD. The non-AP MLD can receive an indication of an association identifier (AID) associated with the non-AP MLD, wherein the indication of the AID indicates whether an AP has BUs for the non-AP MLD, determine one or more links associated with one or more TIDs based on a mapping of a plurality of TIDs, including the one or more TIDs, to a plurality of links, including the one or more links, receive the BUs associated with the one or more TIDs from the AP on the determined links.