A system and method for migrating data objects based on portions of the data objects is described. The system may transfer portions of files, folders, and other data objects from primary storage to secondary storage based on certain criteria, such as time-based criteria, age-based criteria, and so on. An increment may be one or more blocks of a data object, or one or more chunks of a data object, or other segments that combine to form or store a data object. For example, the system identifies one or more blocks of a data object that satisfy a certain criteria, and migrates the identified blocks. The system may determine that a certain number of blocks of a file have not been modified or called by a file system in a certain time period, and migrate these blocks to secondary storage.