Systems and methods for priority inbox notifications and synchronization are disclosed. In some embodiments, a method includes, at a computer system, obtaining message information from a server system. The message information represents a set of messages and an importance score associated with each message in the set of messages. The importance score is generated based at least in part on a global importance prediction model and a user importance prediction model. A new mail notification is presented when a determination is made that the set of messages include one or more unread priority messages. The priority messages comprise messages with which the associated importance score satisfy one or more predefined message importance criteria: Optionally, presentation of a new mail notification is foregone when there is a determination that the set of messages do not include any unread priority messages.