A reliable file system method and system are provided. The reliable file system substantially ensures that an on-media state of a file system is maintained while another working-media state of the file system is modified. At a transaction point, issued by a computer system associated with the file system, the working-media state of the file system is written completely to non-volatile storage associated with the file system. Once the write process is complete, the on-media state of the file system is updated.