Systems and methods for handling of heterogeneous support for Slice Maximum Bit Rate (S-MBR) enforcement are disclosed. In one embodiment, a method performed in a core network of a cellular communications system comprises, at an Access and Mobility Management Function (AMF), obtaining information about whether a Radio Access Network (RAN) node supports S-MBR enforcement and sending, to a Session Management Function (SMF), a message that comprises an indication of whether the RAN node supports S-MBR enforcement. The method further comprises, at the SMF, sending, to a Policy and Control Function (PCF), a message that comprises an indication of whether the RAN node supports S-MBR enforcement. The method further comprises, at the PCF, making a determination of whether to apply a mechanism to enforce S-MBR for Protocol Data Unit (PDU) session of a wireless communication device on a network slice based on the received indication, and operating accordingly.