Systems and methods for dynamic allocation of messaging resources across a hierarchical messaging platform are disclosed. A processing device generates a hierarchical data structure having multiple levels, including a first level of nodes corresponding to respective accounts, a second level of nodes corresponding to respective levels of service, and a third level of nodes corresponding to respective sub-accounts of the accounts. Each node is allocated a respective share of a messaging resource quota associated with its parent node. Each terminal node of the hierarchical data structure is associated with a respective message queue, and each message queue is allocated a corresponding terminal node messaging resource quota. Upon receiving a request from a user of the messaging platform to forward a message to a specified destination, the system identifies the message queue associated with the sub-account of the user and queues the message therein for subsequent forwarding.