This disclosure describes techniques for handling transaction timeouts during setup and management of communication sessions. In particular, a communication device may be configured to handle transaction timeouts differently based on the type of signaling and control message that experienced the transaction timeout. In one aspect, the communication devices may handle transaction timeouts experienced during register transactions differently than transaction timeouts experienced during non-register. For example, the communication device that initiated the transaction initiates at least one subsequent transaction to the current proxy server when a non-register transaction experiences the transaction timeout. After experiencing a threshold number of consecutive transaction timeouts, an expiration of a failure duration timer, or a transaction timeout associated with a register transaction, the communication device cancels the current communication session and sends a register message to a new proxy server.